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Suggestions for the problems around replication of XA in 10.5
by Kristian Nielsen 27 Jan '24

27 Jan '24

Hi Monty, As promised, here my thoughts around the issues with the implementation of replication of external XA as implemented since MariaDB 10.5. I see at least two architectural issues with the current implementation. One is that it splits transactions in two separate GTIDs in the binlog (XA PREPARE and XA COMMIT). This breaks with the fundamental principle that replication applies transactions one after the other in strict sequence, and the replication position/GTID is the single transaction last replicated. This for example means that a mysqldump backup can no longer be used to provision a slave, since any XA PREPAREd event at the time of the dump will be missing; a testcase rpl_xa_provision.test in MDEV-32020 demonstrates this. Another architectural issue is that each XA PREPARE keeps row locks around on every slave until commit (or rollback). This means replication will break if _any_ transaction replicated after the XA PREPARE gets blocked on a lock. This can easily happen; surely in many ways in statement-based replication, and even in row-based replication without primary key as demonstrated by testcase rpl_mdev32020.test in MDEV-32020. There are other problems; for example the update of mysql.gtid_slave_pos cannot be committed crash-safe together with the transaction for XA PREPARE (since the transaction is not committed). I believe the root of the problem is architectural: external XA should be replicated only after they commit on the master. Trying to fix individual problems one by one will not address the root problem and will lead to ever increasing complexity without ever being fully successful. The current implementation appears to only address a very specific and rare use-case, where enhanced semi-synchronous replication is used with row-based binlogging to try to fail-over to a slave and preserve any external XA that was in PREPAREd state on the master before the failover. Mixed-mode replication, provisioning slaves with mysqldump, slaves not intended for failover, etc., seem to be not considered and basically broken since 10.5. Here is my idea for a design that solves most of these problems. At XA PREPARE, we can still write the events to the binlog, but without a GTID, and we do not replicate it to slaves by default. Then at XA COMMIT we binlog a commit transaction that can be replicated normally to the slaves without problems. If necessary, the events for XA COMMIT can be read from the PREPARE earlier in the binlog, eg. after server crash/restart. We already have the binlog checkpoint mechanism to ensure that required binlog files are preserved until no longer needed for transaction recovery. This way we make external XA preserved across server restart, and all normal replication features continue to work - mysqldump, mixed-mode, etc. Nice and simple. Then optionally we can support the specific usecase of being able to recover external XA PREPAREd transactions on a slave after failover. When enabled, the slave can receive the XA PREPARE events and binlog them itself, without applying. Then as part of failover, those XA PREPARE in the binlog that are still pending can be applied, leaving them in PREPAREd state on the new master. This way, _only_ the few transactions that need to be failed-over need special handling, the majority can still just replicate normally. There are different refinements and optimizations that can be added on top of this. But the point is that this is a simple implementation that is robust, correct, and crash-safe from the start, without needing to add complexity and fixes on top. I've done some initial proof-of-concept code for this, and continue to work on it on the branch knielsen_mdev32020 on github. - Kristian.

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Presentation and Interest in "SIMD for SQL Articulations and Capabilities" Undertaking
by Rayan Chowdhury 25 Jan '24

25 Jan '24

Dear MariaDB Developers, I trust this email thinks that you are well. I am Rayan Chowdhury, and I'm an understudy from India as of now seeking Computer Science in NIIT University. I'm excited about the chance to contribute to MariaDB after discovering the "SIMD for SQL Expressions and Functions" project recently. I have a strong fascination with data set frameworks and streamlining, and the objectives of this undertaking adjust impeccably with my goals. Adding vectorized assessment for SQL capabilities and articulations in the MariaDB ColumnStore motor is both captivating and testing, and I'm anxious to be a piece of the work to further develop execution around here. I've started my journey by signing up for the developers' mailing list, and I'm excited to get involved in the MariaDB community. Prior to jumping into commitments, I needed to connect with express my advantage in the undertaking and look for direction on how I can get everything rolling. I'm anticipating adding to MariaDB and gaining from the accomplished designers locally. Much thanks to you for your time, and I'm amped up for the chance of cooperating on this venture. Best respects, Rayan Chowdhury CSE Student, NIIT University

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Re: 1a3974f534f: MDEV-33299 Assertion `(tm->tv_usec % (int) log_10_int[6 - dec]) == 0' failed in void my_timestamp_to_binary(const timeval*, uchar*, uint)
by Sergei Golubchik 24 Jan '24

24 Jan '24

Hi, Alexander, On Jan 24, Alexander Barkov wrote: > revision-id: 1a3974f534f (mariadb-11.3.1-12-g1a3974f534f) > parent(s): 83a79ba33b0 > author: Alexander Barkov > committer: Alexander Barkov > timestamp: 2024-01-23 18:04:31 +0400 > message: > > MDEV-33299 Assertion `(tm->tv_usec % (int) log_10_int[6 - dec]) == 0' failed in void my_timestamp_to_binary(const timeval*, uchar*, uint) > > diff --git a/sql/opt_rewrite_date_cmp.cc b/sql/opt_rewrite_date_cmp.cc > index 5a6410414da..8ff0ab3847e 100644 > --- a/sql/opt_rewrite_date_cmp.cc > +++ b/sql/opt_rewrite_date_cmp.cc > @@ -288,10 +288,13 @@ Item *Date_cmp_func_rewriter::create_end_bound() > const_arg_ts.hour= 23; > const_arg_ts.minute= TIME_MAX_MINUTE; > const_arg_ts.second= TIME_MAX_SECOND; > - const_arg_ts.second_part= TIME_MAX_SECOND_PART; > + const_arg_ts.second_part= TIME_MAX_SECOND_PART - > + my_time_fraction_remainder(TIME_MAX_SECOND_PART, > + field_ref->decimals); > if (check_datetime_range(&const_arg_ts)) > return nullptr; > res= new (thd->mem_root) Item_datetime(thd); > + res->decimals= field_ref->decimals; would it work you if always set res->decimals=6 here (and below)? looks like a simpler way to make the item consistent. > res->set(&const_arg_ts); > break; Regards, Sergei Chief Architect, MariaDB Server and security(a)mariadb.org

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Re: af51be1106b: MDEV-32837 long unique does not work like unique key when using replace
by Sergei Golubchik 24 Jan '24

24 Jan '24

Hi, Alexander, Generally, ok to push. One request for a change and one question below: On Jan 23, Alexander Barkov wrote: > revision-id: af51be1106b (mariadb-10.5.23-57-gaf51be1106b) > parent(s): c9902a20b3a > author: Alexander Barkov > committer: Alexander Barkov > timestamp: 2024-01-17 15:51:54 +0400 > message: > > MDEV-32837 long unique does not work like unique key when using replace > > write_record() when performing REPLACE has an optimization: > - if the unique violation happened in the last unique key, then do UPDATE > - otherwise, do DELETE+INSERT > > This patch skips this optimization in case if a non-versioned table > has hash unique (i.e. UNIQUE..USING HASH) constraints. > > Rationale: > > hash unique constraints are checked before regular unique indexes, > so even if a hash unique is the last unique constraint in the > table->key_info[] array - it guarantees nothing - there still > can be regular (non-hash) contraints that violate as well. > So just go the non-optmized path with DELETE followed > by INSERT on the next loop iteration. Don't forget to update the commit comment to match the final fix. > diff --git a/mysql-test/main/long_unique_bugs_no_protocol.test b/mysql-test/main/long_unique_bugs_no_protocol.test > new file mode 100644 > index 00000000000..a6f1f8e57e8 > --- /dev/null > +++ b/mysql-test/main/long_unique_bugs_no_protocol.test > @@ -0,0 +1,61 @@ > +--source include/no_protocol.inc why no protocol? Regards, Sergei Chief Architect, MariaDB Server and security(a)mariadb.org

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Re: 0c0721cb2f7: MDEV-31616 Problems with a stored function EMPTY() on upgrade to 10.6.
by Sergei Golubchik 22 Jan '24

22 Jan '24

Hi, Alexey, On Dec 27, Alexey Botchkov wrote: > revision-id: 0c0721cb2f7 (mariadb-10.6.16-45-g0c0721cb2f7) > parent(s): aff5ed3988a > author: Alexey Botchkov > committer: Alexey Botchkov > timestamp: 2023-12-19 00:00:48 +0400 > message: > > MDEV-31616 Problems with a stored function EMPTY() on upgrade to 10.6. > > The IDENT_sys doesn't include keywords, so the fucntion with the typo: fucntion > keyword name can be created, but cannot be called. > Moving some keywords to keyword_funcname set so the functions with these > names are allowed. The current logic in the code is: * built-in functions use IDENT_sys (no keywords allowed) in function_call_generic * functions with keyword names are explicitly listed in function_call_conflict. * stored function invocations use IDENT_sys via function_call_generic but * stored function declaration uses sp_name (that is keyword_ident) rule so, it'd make sense to introduce IDENT_funcname and use it instead of IDENT_sys in function_call_generic. That was a good idea. But also, I expect it to make function_call_conflict redundant, because all names from there should be in IDENT_funcname. And the patch doesn't solve the issue that many keywords from IDENT_sys are not in IDENT_funcname. So it's still possible to create functions that cannot be invoked. Note, that simply changing sp_name to use IDENT_funcname is not correct, because stored procedure names have different limitations. Regards, Sergei Chief Architect, MariaDB Server and security(a)mariadb.org

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Re: 02b85f1cf9b: MDEV-31340 Remove MY_COLLATION_HANDLER::strcasecmp()
by Sergei Golubchik 19 Jan '24

19 Jan '24

Hi, Alexander, Phew. It was a big patch. Mostly mechanical changes, admittedly, but still a lot to read. Generally I quite liked it, great work! Shorter way to write an identifier comparison, type safety that enforces namespaces and correct collations. Nice. But there are, of course, comments and questions, please, see below. On Dec 10, Alexander Barkov wrote: > commit 02b85f1cf9b > Author: Alexander Barkov <bar(a)mariadb.com> > Date: Wed Apr 26 15:27:01 2023 +0400 > > MDEV-31340 Remove MY_COLLATION_HANDLER::strcasecmp() > > - Removing the virtual function strnncoll() from MY_COLLATION_HANDLER > > - Adding a wrapper function CHARSET_INFO::streq(), to compare > two strings for equality. For now it calls strnncoll() internally. > In the future it will turn into a virtual function. why would you want it as a virtual function? What is collation-dependent there? > > - Adding new accent sensitive case insensitive collations: > - utf8mb4_general1400_as_ci > - utf8mb3_general1400_as_ci > They implements accent sensitive case insensitive comparison. > The weight of a character is equal to the code point of its > upper case variant. These collation use Unicode-14.0.0 casefolding data. > > The result of > my_charset_utf8mb3_general1400_as_ci.strcoll() > is very close to the former > my_charset_utf8mb3_general_ci.strcasecmp() > > There is only a difference in a couple dozen rare characters, because: > - the switch from "tolower" to "toupper" comparison, to make > utf8mb3_general1400_as_ci closer to utf8mb3_general_ci > - the switch from Unicode-3.0.0 to Unicode-14.0.0 > This difference should be tolarable. See the list of affected > characters in the MDEV description. > > Note, utf8mb4_general1400_as_ci correctly handles non-BMP characters! > Unlike utf8mb4_general_ci, it does not treat all BMP characters > as equal. > > - Adding classes representing names of the file based database objects: > > Lex_ident_db > Lex_ident_table > Lex_ident_trigger > > Their comparison collation depends on the underlying > file system case sensitivity and on --lower-case-table-names > and can be either my_charset_bin or my_charset_utf8mb3_general1400_as_ci. > > - Adding classes representing names of other database objects, > whose names have case insensitive comparison style, > using my_charset_utf8mb3_general1400_as_ci: > > Lex_ident_column > Lex_ident_sys_var > Lex_ident_user_var > Lex_ident_sp_var I don't think Lex_ident_sp_var is a separate domain, it's the same as Lex_ident_column. Both logically: select a from t1 where b > c (here you don't know what's a column and what's an sp var) and also in the code, in fill_spvar_definition() you yourself cast from Lex_ident_sp_var to Lex_ident_column, which kind of defeats the purpose of having two different types and emphasizes that it's actually just one and the same. > Lex_ident_ps > Lex_ident_i_s_table > Lex_ident_window > Lex_ident_func > Lex_ident_partition > Lex_ident_with_element > Lex_ident_rpl_filter > Lex_ident_master_info > Lex_ident_host > Lex_ident_locale > Lex_ident_plugin > Lex_ident_engine > Lex_ident_server > Lex_ident_savepoint > Lex_ident_table_option_name > Lex_ident_table_option_value option value is a string, not an ident > Lex_ident_charset > > - All the mentioned Lex_ident_xxx classes implement a method streq(): > > if (ident1.streq(ident2)) > do_equal(); > > This method works as a wrapper for CHARSET_INFO::streq(). > > - Changing a lot of "LEX_CSTRING name" to "Lex_ident_xxx name" > in class members and in function/method parameters. > > - Replacing all calls like > system_charset_info->coll->strcasecmp(ident1, ident2) > to > ident1.streq(ident2) > > - Taking advantage of the c++11 user defined literal operator > for Lex_ident_xxx data type. See lex_ident.h. > Use example: > > const Lex_ident_column primary_key_name= "PRIMARY"_Lex_ident_column; > > is now a shorter version of: > > const Lex_ident_column primary_key_name= > Lex_ident_column({STRING_WITH_LEN("PRIMARY")}); Of all the things in your patch this will be the first thing that Monty will remove when he'll stumble upon it. Could you instead implement a constructor that understands const Lex_ident_column primary_key_name= {STRING_WITH_LEN("PRIMARY")}; > diff --git a/include/m_ctype.h b/include/m_ctype.h > index 9d13989d1fe..e5c5145b256 100644 > --- a/include/m_ctype.h > +++ b/include/m_ctype.h > @@ -997,6 +1006,18 @@ struct charset_info_st > return state & MY_CS_COMPILED; > } > > + /* > + There will be a separate virtual function streq() in > + MY_COLLATION_HANDLER eventually. > + */ > + my_bool streq(const LEX_CSTRING a, const LEX_CSTRING b) const > + { > + DBUG_ASSERT(is_valid_comparison_operand(a)); > + DBUG_ASSERT(is_valid_comparison_operand(b)); > + return 0 == (coll->strnncoll)(this, (const uchar *) a.str, a.length, > + (const uchar *) b.str, b.length, FALSE); as you have also added strnncoll helper, you can write the above as return 0 == strnncoll(a, b); also, perhaps you should move these asserts into strnncoll helper? > + } > + > int strnncoll(const uchar *a, size_t alen, > const uchar *b, size_t blen, my_bool b_is_prefix= FALSE) const > { > diff --git a/mysql-test/main/ctype_utf8mb4_general1400_as_ci_casefold.result b/mysql-test/main/ctype_utf8mb4_general1400_as_ci_casefold.result > new file mode 100644 > index 00000000000..c6ccf662d16 > --- /dev/null > +++ b/mysql-test/main/ctype_utf8mb4_general1400_as_ci_casefold.result > @@ -0,0 +1,1446 @@ > +# > +# Start of 11.4 tests > +# > +# > +# MDEV-31340 Remove MY_COLLATION_HANDLER::strcasecmp() > +# > +SET NAMES utf8mb4 COLLATE utf8mb4_general1400_as_ci; > +EXECUTE IMMEDIATE SFORMAT(' > +CREATE VIEW v_bmp AS > +SELECT > + seq AS codepoint, > + LPAD(HEX(seq),4,''0'') AS codepoint_hex4, > + CONVERT(CHAR(seq USING utf32) USING {}) COLLATE {} AS c > +FROM > + seq_0_to_65535', @@character_set_connection, @@collation_connection); > +SELECT COLLATION(c) FROM v_bmp LIMIT 1; > +COLLATION(c) > +utf8mb4_general1400_as_ci > +SELECT > +codepoint_hex4, > +HEX(CAST(LOWER(c) AS CHAR CHARACTER SET ucs2)), > +HEX(CAST(UPPER(c) AS CHAR CHARACTER SET ucs2)) > +FROM v_bmp > +WHERE BINARY(c)<>BINARY(LOWER(c)) OR BINARY(c)<>BINARY(UPPER(c)); > +codepoint_hex4 HEX(CAST(LOWER(c) AS CHAR CHARACTER SET ucs2)) HEX(CAST(UPPER(c) AS CHAR CHARACTER SET ucs2)) what is the point of this table? detect changes when going to the next unicode version? > +0041 0061 0041 ... > +# > +# End of 11.4 tests > +# > diff --git a/mysql-test/main/ctype_utf8mb4_general1400_as_ci_ws.result b/mysql-test/main/ctype_utf8mb4_general1400_as_ci_ws.result > new file mode 100644 > index 00000000000..49f43777feb > --- /dev/null > +++ b/mysql-test/main/ctype_utf8mb4_general1400_as_ci_ws.result > diff --git a/mysql-test/main/ctype_utf8mb4_general1400_as_ci_ws.test b/mysql-test/main/ctype_utf8mb4_general1400_as_ci_ws.test > new file mode 100644 > index 00000000000..b5eb369ae9a > --- /dev/null > +++ b/mysql-test/main/ctype_utf8mb4_general1400_as_ci_ws.test > @@ -0,0 +1,39 @@ > +--source include/have_utf32.inc > +--source include/have_sequence.inc > + > +--echo # > +--echo # Start of 11.1 tests > +--echo # > + > +--echo # > +--echo # Collation utfmb4_general1400_as_ci > +--echo # > + > +SET NAMES utf8mb4 COLLATE utf8mb4_general1400_as_ci; > + > +EXECUTE IMMEDIATE SFORMAT(' > +CREATE VIEW v_bmp AS > +SELECT > + seq AS codepoint, > + LPAD(HEX(seq),6,''0'') AS codepoint_hex6, > + CONVERT(CHAR(seq USING utf32) USING {}) COLLATE {} AS c > +FROM > + seq_0_to_1114111', @@character_set_connection, @@collation_connection); > + > +SELECT COLLATION(c) FROM v_bmp LIMIT 1; > + > +SELECT > + SUM(codepoint_hex6=HEX(LOWER(c))) AS count_bmp_weight_is_lower, > + SUM(codepoint_hex6<>HEX(LOWER(c))) AS count_bmp_weight_is_not_lower > +FROM v_bmp; > + > +SELECT codepoint_hex6,HEX(WEIGHT_STRING(c)) > +FROM v_bmp > +WHERE codepoint_hex6<>HEX(WEIGHT_STRING(c)); > + > +DROP VIEW v_bmp; > + > + > +--echo # > +--echo # End of 11.1 tests 11.4 ? > +--echo # > diff --git a/mysql-test/suite/compat/oracle/r/lower_case_table_names.result b/mysql-test/suite/compat/oracle/r/lower_case_table_names.result > new file mode 100644 > index 00000000000..2518be31402 > --- /dev/null > +++ b/mysql-test/suite/compat/oracle/r/lower_case_table_names.result > @@ -0,0 +1,9 @@ > +SELECT @@lower_case_table_names; > +@@lower_case_table_names > +1 > +# > +# TODO: Report this problem as MDEV what is the problem? isn't the comparison accent-sensitive? > +# > +SET NAMES utf8; > +CREATE TABLE t1 (a öracle_schema.date); > +ERROR HY000: Unknown data type: 'öracle_schema.date' > diff --git a/mysql-test/suite/unit/disabled.def b/mysql-test/suite/unit/disabled.def > new file mode 100644 > index 00000000000..3a68bea32d0 > --- /dev/null > +++ b/mysql-test/suite/unit/disabled.def > @@ -0,0 +1,12 @@ > +############################################################################## > +# > +# List the test cases that are to be disabled temporarily. > +# > +# Separate the test case name and the comment with ':'. > +# > +# <testcasename> : BUG#<xxxx> <date disabled> <disabler> <comment> > +# > +# Do not use any TAB characters for whitespace. > +# > +############################################################################## > +conc_charset : TODO: client side ID for utf8mb4_tolower_ci 1. There is no utf8mb4_tolower_ci 2. what do you mean "client side ID"? > diff --git a/sql/ddl_log.cc b/sql/ddl_log.cc > index 61c8f50d1e3..fdfb605a57f 100644 > --- a/sql/ddl_log.cc > +++ b/sql/ddl_log.cc > @@ -1146,22 +1146,23 @@ static void execute_rename_table(DDL_LOG_ENTRY *ddl_log_entry, handler *file, > static void rename_triggers(THD *thd, DDL_LOG_ENTRY *ddl_log_entry, > bool swap_tables) > { > - LEX_CSTRING to_table, from_table, to_db, from_db, from_converted_name; > + Lex_ident_table to_table, from_table, from_converted_name; > + Lex_ident_db to_db, from_db; > char to_path[FN_REFLEN+1], from_path[FN_REFLEN+1], conv_path[FN_REFLEN+1]; > > if (!swap_tables) > { > - from_db= ddl_log_entry->db; > - from_table= ddl_log_entry->name; > - to_db= ddl_log_entry->from_db; > - to_table= ddl_log_entry->from_name; > + from_db= Lex_ident_db(ddl_log_entry->db); this would look better with implicit casting, that is, if you'd have an assignment operator from LEX_CSTRING > + from_table= Lex_ident_table(ddl_log_entry->name); > + to_db= Lex_ident_db(ddl_log_entry->from_db); > + to_table= Lex_ident_table(ddl_log_entry->from_name); > } > else > { > - from_db= ddl_log_entry->from_db; > - from_table= ddl_log_entry->from_name; > - to_db= ddl_log_entry->db; > - to_table= ddl_log_entry->extra_name; > + from_db= Lex_ident_db(ddl_log_entry->from_db); > + from_table= Lex_ident_table(ddl_log_entry->from_name); > + to_db= Lex_ident_db(ddl_log_entry->db); > + to_table= Lex_ident_table(ddl_log_entry->extra_name); > } > > build_filename_and_delete_tmp_file(from_path, sizeof(from_path), > @@ -1211,11 +1212,11 @@ static void rename_triggers(THD *thd, DDL_LOG_ENTRY *ddl_log_entry, > > (void) Table_triggers_list::prepare_for_rename(thd, > &trigger_param, > - &from_db, > - &from_table, > - &from_converted_name, > - &to_db, > - &to_table); > + from_db, > + from_table, > + from_converted_name, > + to_db, > + to_table); You rather inconsistently replace pointers with const references in some methods, like above, but not in others, like below or in the next hunk. > (void) Table_triggers_list::change_table_name(thd, > &trigger_param, > &from_db, > @@ -1707,9 +1708,8 @@ static int ddl_log_execute_action(THD *thd, MEM_ROOT *mem_root, > > switch (ddl_log_entry->phase) { > case DDL_DROP_DB_PHASE_INIT: > - drop_database_objects(thd, &path, &db, > - !my_strcasecmp(system_charset_info, > - MYSQL_SCHEMA_NAME.str, db.str)); > + // QQ: was a bug here? This comment makes little sense in the code, as one cannot see what *was* here before. Just drop it. > + drop_database_objects(thd, &path, &db, MYSQL_SCHEMA_NAME.streq(db)); > > strxnmov(to_path, sizeof(to_path)-1, path.str, MY_DB_OPT_FILE, NullS); > mysql_file_delete_with_symlink(key_file_misc, to_path, "", MYF(0)); > diff --git a/sql/debug_sync.cc b/sql/debug_sync.cc > index 362463a7f22..4704691615a 100644 > --- a/sql/debug_sync.cc > +++ b/sql/debug_sync.cc > @@ -858,6 +858,13 @@ static st_debug_sync_action *debug_sync_get_action(THD *thd, > } > > > +class Debug_token: public Lex_ident_ci > +{ > +public: > + using Lex_ident_ci::Lex_ident_ci; > +}; I wonder if you can create those types with less boilerplate will typedef work? will using work? if not, may be, like template<> Lex_ident_templ: Lex_ident_ci { ... } Lex_ident_templ<> Debug_token; > + > + > /** > Set a debug sync action. > > @@ -909,7 +916,8 @@ static bool debug_sync_set_action(THD *thd, st_debug_sync_action *action) > } > else > { > - const char *dsp_name= action->sync_point.c_ptr(); > + const Debug_token dsp_name(action->sync_point.c_ptr(), > + action->sync_point.length()); or dsp_name(action->sync_point->to_lex_cstring()) ? > #ifdef DBUG_TRACE > DBUG_EXECUTE("debug_sync", { > /* Functions as DBUG_PRINT args can change keyword and line nr. */ > diff --git a/sql/grant.cc b/sql/grant.cc > index 1ba197bc1d9..0ebf47431bc 100644 > --- a/sql/grant.cc > +++ b/sql/grant.cc > @@ -31,8 +31,8 @@ bool Grant_privilege::add_column_privilege(THD *thd, > class LEX_COLUMN *point; > while ((point=iter++)) > { > - if (!my_strcasecmp(system_charset_info, > - point->column.c_ptr(), new_str->c_ptr())) > + const Lex_ident_column tmp(point->column.c_ptr(), point->column.length()); That feels like an overkill, creating Lex_ident_column just to compare two strings. What is it compiled to at -O3? > + if (tmp.streq(new_str->to_lex_cstring())) > break; > } > m_column_privilege_total|= which_grant; > diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc > index a615d26b9a9..fc840c21191 100644 > --- a/sql/ha_partition.cc > +++ b/sql/ha_partition.cc > @@ -118,7 +118,7 @@ int ha_partition::notify_tabledef_changed(LEX_CSTRING *db, > LEX_CSTRING table_name; > const char *table_name_ptr; > if (create_partition_name(from_buff, sizeof(from_buff), > - from_path, name_buffer_ptr, > + from_path, Lex_cstring_strlen(name_buffer_ptr), Don't, please. You _always_ use Lex_cstring_strlen, in _all_ invocations of create_partition_name(). Just pass a char* down as before and do strlen inside, if you need it. > NORMAL_PART_NAME, FALSE)) > res=1; > table_name_ptr= from_buff + dirname_length(from_buff); > diff --git a/sql/handler.cc b/sql/handler.cc > index a977054d0da..7b9d11d00a2 100644 > --- a/sql/handler.cc > +++ b/sql/handler.cc > @@ -7531,7 +7528,8 @@ int handler::check_duplicate_long_entry_key(const uchar *new_rec, uint key_no) > else > { > Item_func_left *fnc= static_cast<Item_func_left *>(arguments[j]); > - DBUG_ASSERT(!my_strcasecmp(system_charset_info, "left", fnc->func_name())); > + DBUG_ASSERT(Lex_ident_func(fnc->func_name_cstring()). eh, why func_name_cstring() doesn't return Lex_ident_func? > + streq("left"_Lex_cstring)); > DBUG_ASSERT(fnc->arguments()[0]->type() == Item::FIELD_ITEM); > t_field= static_cast<Item_field *>(fnc->arguments()[0])->field; > uint length= (uint)fnc->arguments()[1]->val_int(); > diff --git a/sql/item.cc b/sql/item.cc > index 5c4f1704ebe..5689756eca9 100644 > --- a/sql/item.cc > +++ b/sql/item.cc > @@ -3463,13 +3463,11 @@ bool Item_field::eq(const Item *item, bool binary_cmp) const > (In cases where we would choose wrong we would have to generate a > ER_NON_UNIQ_ERROR). > */ > - return (!lex_string_cmp(system_charset_info, &item_field->name, > - &field_name) && > - (!item_field->table_name.str || !table_name.str || > - (!my_strcasecmp(table_alias_charset, item_field->table_name.str, > - table_name.str) && > - (!item_field->db_name.str || !db_name.str || > - (item_field->db_name.str && !strcmp(item_field->db_name.str, > + return (item_field->name.streq(field_name) && > + (!item_field->table_name.str || !table_name.str || > + (item_field->table_name.streq(table_name) && > + (!item_field->db_name.str || !db_name.str || > + (item_field->db_name.str && !strcmp(item_field->db_name.str, > db_name.str)))))); I presume, # db_name should also be compared with streq > } > > diff --git a/sql/item_create.cc b/sql/item_create.cc > index 4f0df8f732d..501db19c1b8 100644 > --- a/sql/item_create.cc > +++ b/sql/item_create.cc > @@ -2638,7 +2639,8 @@ Create_qfunc::create_func(THD *thd, const LEX_CSTRING *name, > if (thd->lex->copy_db_to(&db)) > return NULL; > > - return create_with_db(thd, &db, name, false, item_list); Again, can LEX_CSTRING be implicitly cast to the correct Lex_ident variant? > + return create_with_db(thd, Lex_ident_db(db), Lex_ident_func(*name), > + false, item_list); > } > > > diff --git a/sql/item_windowfunc.cc b/sql/item_windowfunc.cc > index 5438cade27a..f0a5737bdf7 100644 > --- a/sql/item_windowfunc.cc > +++ b/sql/item_windowfunc.cc > @@ -28,7 +28,7 @@ Item_window_func::resolve_window_name(THD *thd) > return false; > } > DBUG_ASSERT(window_name != NULL && window_spec == NULL); > - const char *ref_name= window_name->str; > + const LEX_CSTRING &ref_name= *window_name; Why LEX_CSTRING ? > > /* !TODO: Add the code to resolve ref_name in outer queries */ > /* > diff --git a/sql/opt_trace.cc b/sql/opt_trace.cc > index 1008690ccaa..dbb2708f487 100644 > --- a/sql/opt_trace.cc > +++ b/sql/opt_trace.cc > @@ -43,7 +43,7 @@ bool list_has_optimizer_trace_table(const TABLE_LIST *tbl) > for (; tbl; tbl= tbl->next_global) > { > if (tbl->schema_table && > - 0 == strcmp(tbl->schema_table->table_name, I_S_table_name)) > + 0 == strcmp(tbl->schema_table->table_name.str, I_S_table_name)) Why not streq? > return true; > } > return false; > @@ -190,9 +190,8 @@ void opt_trace_disable_if_no_security_context_access(THD *thd) > if (!(thd->main_security_ctx.check_access(GLOBAL_ACLS & ~GRANT_ACL)) && > (0 != strcmp(thd->main_security_ctx.priv_user, > thd->security_context()->priv_user) || > - 0 != my_strcasecmp(system_charset_info, > - thd->main_security_ctx.priv_host, > - thd->security_context()->priv_host))) > + !Lex_ident_host(Lex_cstring_strlen(thd->main_security_ctx.priv_host)). > + streq(Lex_cstring_strlen(thd->security_context()->priv_host)))) Doesn't really look like an improvement :) May be you can get rid of intermediate Lex_cstring_strlen()'s ? > trace->missing_privilege(); > } > > diff --git a/sql/partition_info.cc b/sql/partition_info.cc > index 1b65de6e3c0..7b76c6d65b1 100644 > --- a/sql/partition_info.cc > +++ b/sql/partition_info.cc > @@ -1403,8 +1397,8 @@ bool partition_info::check_partition_info(THD *thd, handlerton **eng_type, > num_parts_not_set++; > part_elem->engine_type= default_engine_type; > } > - if (check_table_name(part_elem->partition_name, > - strlen(part_elem->partition_name), FALSE)) > + if (check_table_name(part_elem->partition_name.str, > + part_elem->partition_name.length, FALSE)) better change check_table_name to accept a LEX_CSTRING or Lex_ident, it'll simplify almost all (except one) invocations of it > { > my_error(ER_WRONG_PARTITION_NAME, MYF(0)); > goto end; > @@ -2604,8 +2596,8 @@ bool partition_info::has_same_partitioning(partition_info *new_part_info) > part_state must be PART_NORMAL! > */ > if (!part_elem || !new_part_elem || > - strcmp(part_elem->partition_name, > - new_part_elem->partition_name) || > + strcmp(part_elem->partition_name.str, > + new_part_elem->partition_name.str) || why strcmp? > part_elem->part_state != PART_NORMAL || > new_part_elem->part_state != PART_NORMAL || > part_elem->max_value != new_part_elem->max_value || > @@ -2666,8 +2658,8 @@ bool partition_info::has_same_partitioning(partition_info *new_part_info) > sub_part_elem->engine_type != new_sub_part_elem->engine_type) > DBUG_RETURN(false); > > - if (strcmp(sub_part_elem->partition_name, > - new_sub_part_elem->partition_name) || > + if (strcmp(sub_part_elem->partition_name.str, > + new_sub_part_elem->partition_name.str) || same here > sub_part_elem->part_state != PART_NORMAL || > new_sub_part_elem->part_state != PART_NORMAL || > sub_part_elem->part_min_rows != > diff --git a/sql/partition_info.h b/sql/partition_info.h > index 3a8c3a37524..92e8906274f 100644 > --- a/sql/partition_info.h > +++ b/sql/partition_info.h > @@ -526,11 +527,13 @@ void partition_info::vers_update_el_ids() > } > > > -inline > -bool make_partition_name(char *move_ptr, uint i) > +static inline > +Lex_ident_partition make_partition_name_ls(char *move_ptr, uint i) it's not _ls really, is it? why not to keep the old name? > { > int res= snprintf(move_ptr, MAX_PART_NAME_SIZE + 1, "p%u", i); > - return res < 0 || res > MAX_PART_NAME_SIZE; > + return res < 0 || res > MAX_PART_NAME_SIZE ? > + Lex_ident_partition() : > + Lex_ident_partition(move_ptr, (size_t) res); > } > > > @@ -549,15 +552,16 @@ uint partition_info::next_part_no(uint new_parts) const > for (uint cur_part= 0; cur_part < new_parts; ++cur_part, ++suffix) > { > uint32 cur_suffix= suffix; > - if (make_partition_name(part_name, suffix)) > + Lex_ident_partition part_name_ls(make_partition_name_ls(part_name, suffix)); > + if (!part_name_ls.str) > return 0; > partition_element *el; > it.rewind(); > while ((el= it++)) > { > - if (0 == my_strcasecmp(&my_charset_latin1, el->partition_name, part_name)) > + if (el->partition_name.streq(part_name_ls)) > { > - if (make_partition_name(part_name, ++suffix)) > + if (!(part_name_ls= make_partition_name_ls(part_name, ++suffix)).str) you don't seem to use part_name_ls below > return 0; > it.rewind(); > } > diff --git a/sql/set_var.h b/sql/set_var.h > index aed4955ef62..8f7e3609f5f 100644 > --- a/sql/set_var.h > +++ b/sql/set_var.h > @@ -383,7 +383,7 @@ class set_var_default_role: public set_var_base > { > LEX_USER *user, *real_user; > LEX_CSTRING role; > - const char *real_role; > + LEX_CSTRING real_role; Not Lex_ident_user ? > public: > set_var_default_role(LEX_USER *user_arg, LEX_CSTRING role_arg) : > user(user_arg), role(role_arg) {} > diff --git a/sql/slave.cc b/sql/slave.cc > index 0a15cc55146..daeb05f423e 100644 > --- a/sql/slave.cc > +++ b/sql/slave.cc > @@ -3403,8 +3403,9 @@ static bool send_show_master_info_data(THD *thd, Master_info *mi, bool full, > static int cmp_mi_by_name(const Master_info **arg1, > const Master_info **arg2) > { > - return my_strcasecmp(system_charset_info, (*arg1)->connection_name.str, > - (*arg2)->connection_name.str); > + return Lex_ident_master_info::charset_info()->strnncoll( > + (*arg1)->connection_name, > + (*arg2)->connection_name); Why not (*arg1)->connection_name.streq() ? > } > > > diff --git a/sql/sp_pcontext.cc b/sql/sp_pcontext.cc > index 848d1f0c655..761f535832d 100644 > --- a/sql/sp_pcontext.cc > +++ b/sql/sp_pcontext.cc > @@ -139,8 +139,7 @@ sp_pcontext *sp_pcontext::push_context(THD *thd, sp_pcontext::enum_scope scope) > > bool cmp_labels(sp_label *a, sp_label *b) > { > - return (lex_string_cmp(system_charset_info, &a->name, &b->name) == 0 && > - a->type == b->type); > + return a->name.streq(b->name) && a->type == b->type; put type comparison first, please > } > > sp_pcontext *sp_pcontext::pop_context() > diff --git a/sql/sql_acl.cc b/sql/sql_acl.cc > index 09af5523c76..dd36504ed56 100644 > --- a/sql/sql_acl.cc > +++ b/sql/sql_acl.cc > @@ -567,14 +560,17 @@ static uchar* acl_role_get_key(ACL_ROLE *entry, size_t *length, > > struct ROLE_GRANT_PAIR : public Sql_alloc > { > - char *u_uname; > - char *u_hname; > - char *r_uname; > + LEX_CSTRING u_uname; > + LEX_CSTRING u_hname; > + LEX_CSTRING r_uname; Lex_ident_user ? (and in many places below) > LEX_STRING hashkey; > bool with_admin; > > - bool init(MEM_ROOT *mem, const char *username, const char *hostname, > - const char *rolename, bool with_admin_option); > + bool init(MEM_ROOT *mem, > + const LEX_CSTRING &username, > + const LEX_CSTRING &hostname, > + const LEX_CSTRING &rolename, > + bool with_admin_option); > }; > > static uchar* acl_role_map_get_key(ROLE_GRANT_PAIR *entry, size_t *length, > @@ -2731,7 +2733,7 @@ static bool acl_load(THD *thd, const Grant_tables& tables) > char *db_name; > db.user=safe_str(get_field(&acl_memroot, db_table.user())); > const char *hostname= get_field(&acl_memroot, db_table.host()); > - if (!hostname && find_acl_role(db.user, true)) > + if (!hostname && find_acl_role(Lex_cstring_strlen(db.user), true)) Perhaps it'd be better to change user and db to be Lex_ident_* in ACL_DB? > hostname= ""; > update_hostname(&db.host, hostname); > db.db= db_name= get_field(&acl_memroot, db_table.db()); > @@ -2822,14 +2824,29 @@ static bool acl_load(THD *thd, const Grant_tables& tables) > init_alloc_root(key_memory_acl_mem, &temp_root, ACL_ALLOC_BLOCK_SIZE, 0, MYF(0)); > while (!(read_record_info.read_record())) > { > - char *hostname= safe_str(get_field(&temp_root, roles_mapping_table.host())); > - char *username= safe_str(get_field(&temp_root, roles_mapping_table.user())); > - char *rolename= safe_str(get_field(&temp_root, roles_mapping_table.role())); > + StringBuffer<MAX_FIELD_WIDTH> host_buff, user_buff, role_buff; > + /* > + find_user_by_name() called recursively later in this code block There's no find_user_by_name() and acl_find_user_by_name does not seem to be called recursively. What did you mean here? also, why you didn't change acl_find_user_by_name to take a Lex_ident? > + needs a 0-terminated string. So does sql_print_error(). > + As val_lex_cstring() does not guarantee a 0-terminated string, > + let's alloc 0-terminated copies of val_lex_cstring() results on > + the memory root. you've already added Field::val_lex_string_strmake() in August, why not to use it here? > + */ > + const Lex_cstring hostname= safe_lexcstrdup_root(&temp_root, > + roles_mapping_table.host()-> > + val_lex_cstring(&host_buff)); > + const Lex_cstring username= safe_lexcstrdup_root(&temp_root, > + roles_mapping_table.user()-> > + val_lex_cstring(&user_buff)); > + const Lex_cstring rolename= safe_lexcstrdup_root(&temp_root, > + roles_mapping_table.role()-> > + val_lex_cstring(&role_buff)); > + > bool with_grant_option= get_YN_as_bool(roles_mapping_table.admin_option()); > > if (add_role_user_mapping(username, hostname, rolename)) { > sql_print_error("Invalid roles_mapping table entry user:'%s@%s', rolename:'%s'", > - username, hostname, rolename); > + username.str, hostname.str, rolename.str); > continue; > } > > @@ -4443,28 +4484,31 @@ static ACL_USER * find_user_wild(const char *host, const char *user, const char > /* > Find a role with the specified name > */ > -static ACL_ROLE *find_acl_role(const char *role, bool allow_public) > +static ACL_ROLE *find_acl_role(const LEX_CSTRING &role, bool allow_public) > { > - size_t length= strlen(role); > DBUG_ENTER("find_acl_role"); > - DBUG_PRINT("enter",("role: '%s'", role)); > + DBUG_PRINT("enter",("role: '%s'", role.str)); > DBUG_PRINT("info", ("Hash elements: %ld", acl_roles.records)); > > mysql_mutex_assert_owner(&acl_cache->lock); > > - if (!length || (!allow_public && strcasecmp(role, public_name.str) == 0)) > + if (!role.length || > + (!allow_public && > + my_charset_utf8mb3_general1400_as_ci.streq(role, public_name))) Lex_ident_user would've been nice here too > DBUG_RETURN(NULL); > > - ACL_ROLE *r= (ACL_ROLE *)my_hash_search(&acl_roles, (uchar *)role, length); > + ACL_ROLE *r= (ACL_ROLE *)my_hash_search(&acl_roles, (uchar *)role.str, > + role.length); > DBUG_RETURN(r); > } > > /* > Finds a grantee - something that privileges or roles can be granted to. > */ > -static ACL_USER_BASE *find_acl_user_base(const char *user, const char *host) > +static ACL_USER_BASE *find_acl_user_base(const LEX_CSTRING &user, > + const LEX_CSTRING &host) > { > - if (*host) > + if (*host.str) > return find_user_exact(host, user); > > return find_acl_role(user, true); > @@ -5657,8 +5696,8 @@ static GRANT_NAME *name_hash_search(HASH *name_hash, > { > if (!grant_name->host.hostname || > (host && > - !my_strcasecmp(system_charset_info, host, > - grant_name->host.hostname)) || > + Lex_ident_host(Lex_cstring_strlen(host)). Still don't like these Lex_ident_something(Lex_cstring_strlen(xxx)) Let's get rid of them > + streq(Lex_cstring_strlen(grant_name->host.hostname))) || > (ip && !strcmp(ip, grant_name->host.hostname))) > return grant_name; > } > @@ -7373,8 +7414,9 @@ int mysql_table_grant(THD *thd, TABLE_LIST *table_list, > } > } > if (Str->is_role()) > - propagate_role_grants(find_acl_role(Str->user.str, true), > - PRIVS_TO_MERGE::TABLE_COLUMN, db_name, table_name); > + propagate_role_grants(find_acl_role(Str->user, true), > + PRIVS_TO_MERGE::TABLE_COLUMN, > + db_name.str, table_name.str); may be pass Lex_ident_* down into propagate_role_grants too? > } > > thd->mem_root= old_root; > diff --git a/sql/sql_base.cc b/sql/sql_base.cc > index 9d2415d3a4d..d7d7ebee024 100644 > --- a/sql/sql_base.cc > +++ b/sql/sql_base.cc > @@ -233,33 +233,41 @@ uint get_table_def_key(const TABLE_LIST *table_list, const char **key) > # Pointer to list of names of open tables. > */ > > -struct list_open_tables_arg > +class list_open_tables_arg > { > +public: > THD *thd; > - const char *db; > + const Lex_ident_db db; > const char *wild; > TABLE_LIST table_list; > OPEN_TABLE_LIST **start_list, *open_list; > + > + list_open_tables_arg(THD *thd_arg, const LEX_CSTRING &db_arg, > + const char *wild_arg) > + :thd(thd_arg), db(db_arg), wild(wild_arg), > + start_list(&open_list), open_list(0) > + { > + bzero((char*) &table_list, sizeof(table_list)); > + } > }; > > > static my_bool list_open_tables_callback(TDC_element *element, > list_open_tables_arg *arg) > { > - const char *db= (char*) element->m_key; > - size_t db_length= strlen(db); > - const char *table_name= db + db_length + 1; > + const Lex_ident_db > + db= Lex_ident_db(Lex_cstring_strlen((const char*) element->m_key)); > + const char *table_name= db.str + db.length + 1; > > - if (arg->db && my_strcasecmp(system_charset_info, arg->db, db)) > + // QQ: a bug was here? same as above, "was" > + if (arg->db.str && !arg->db.streq(db)) > return FALSE; > if (arg->wild && wild_compare(table_name, arg->wild, 0)) > return FALSE; > > /* Check if user has SELECT privilege for any column in the table */ > - arg->table_list.db.str= db; > - arg->table_list.db.length= db_length; > - arg->table_list.table_name.str= table_name; > - arg->table_list.table_name.length= strlen(table_name); > + arg->table_list.db= db; > + arg->table_list.table_name= Lex_cstring_strlen(table_name); > arg->table_list.grant.privilege= NO_ACL; > > if (check_table_access(arg->thd, SELECT_ACL, &arg->table_list, TRUE, 1, TRUE)) > @@ -1906,7 +1904,7 @@ bool open_table(THD *thd, TABLE_LIST *table_list, Open_table_context *ot_ctx) > DBUG_ASSERT(!table_list->table); > > /* an open table operation needs a lot of the stack space */ > - if (check_stack_overrun(thd, STACK_MIN_SIZE_FOR_OPEN, (uchar *)&alias)) > + if (check_stack_overrun(thd, STACK_MIN_SIZE_FOR_OPEN, (uchar *)&alias.str)) better pass `key` above. doesn't matter much but looks a bit less weird > DBUG_RETURN(TRUE); > > if (!(flags & MYSQL_OPEN_IGNORE_KILLED) && thd->killed) > @@ -1954,7 +1952,10 @@ bool open_table(THD *thd, TABLE_LIST *table_list, Open_table_context *ot_ctx) > if (table->s->table_cache_key.length == key_length && > !memcmp(table->s->table_cache_key.str, key, key_length)) > { > - if (!my_strcasecmp(system_charset_info, table->alias.c_ptr(), alias) && > + // QQ: Why table_alias_charset is not used for comparison? Did you try to correct this? > + if (my_charset_utf8mb3_general1400_as_ci.streq( > + table->alias.to_lex_cstring(), > + alias) && > table->query_id != thd->query_id && /* skip tables already used */ > (thd->locked_tables_mode == LTM_LOCK_TABLES || > table->query_id == 0)) > @@ -6353,26 +6355,25 @@ find_field_in_natural_join(THD *thd, TABLE_LIST *table_ref, const char *name, si > */ > > Field * > -find_field_in_table(THD *thd, TABLE *table, const char *name, size_t length, > +find_field_in_table(THD *thd, TABLE *table, const Lex_ident_column &name, > bool allow_rowid, field_index_t *cached_field_index_ptr) > { > Field *field; > field_index_t cached_field_index= *cached_field_index_ptr; > DBUG_ENTER("find_field_in_table"); > DBUG_PRINT("enter", ("table: '%s', field name: '%s'", table->alias.c_ptr(), > - name)); > + name.str)); > > /* We assume here that table->field < NO_CACHED_FIELD_INDEX = UINT_MAX */ > if (cached_field_index < table->s->fields && > - !my_strcasecmp(system_charset_info, > - table->field[cached_field_index]->field_name.str, name)) > + table->field[cached_field_index]->field_name.streq(name)) > { > field= table->field[cached_field_index]; > DEBUG_SYNC(thd, "table_field_cached"); > } > else > { > - LEX_CSTRING fname= {name, length}; > + LEX_CSTRING fname= name; Do you need that? You can use `name` directly below > field= table->find_field_by_name(&fname); > } > > @@ -6999,9 +7000,9 @@ find_item_in_list(Item *find, List<Item> &items, uint *counter, > List_iterator<Item> li(items); > uint n_items= limit == 0 ? items.elements : limit; > Item **found=0, **found_unaliased= 0, *item; > - const char *db_name=0; > + const LEX_CSTRING *db_name=0; > const LEX_CSTRING *field_name= 0; > - const char *table_name=0; > + const LEX_CSTRING *table_name=0; Why not Lex_ident's ? > bool found_unaliased_non_uniq= 0; > /* > true if the item that we search for is a valid name reference > @@ -7059,12 +7060,11 @@ find_item_in_list(Item *find, List<Item> &items, uint *counter, > item is not fix_field()'ed yet. > */ > if (item_field->field_name.str && item_field->table_name.str && > - !lex_string_cmp(system_charset_info, &item_field->field_name, > - field_name) && > - !my_strcasecmp(table_alias_charset, item_field->table_name.str, > - table_name) && > - (!db_name || (item_field->db_name.str && > - !strcmp(item_field->db_name.str, db_name)))) > + item_field->field_name.streq(*field_name) && > + item_field->table_name.streq(*table_name) && > + (!db_name || !db_name->str || > + (item_field->db_name.str && > + !strcmp(item_field->db_name.str, db_name->str)))) why strcmp? > { > if (found_unaliased) > { > @@ -7135,11 +7132,10 @@ find_item_in_list(Item *find, List<Item> &items, uint *counter, > } > } > } > - else if (!table_name) > + else if (!table_name || !table_name->str) > { > if (is_ref_by_name && find->name.str && item->name.str && > - find->name.length == item->name.length && > - !lex_string_cmp(system_charset_info, &item->name, &find->name)) > + item->name.streq(find->name)) Do you have tests that will fail if streq will compare lengths? > { > found= li.ref(); > *counter= i; > diff --git a/sql/sql_class.cc b/sql/sql_class.cc > index a2414de645b..1b36cd9416f 100644 > --- a/sql/sql_class.cc > +++ b/sql/sql_class.cc > @@ -855,10 +853,13 @@ THD::THD(my_thread_id id, bool is_wsrep_applier) > profiling.set_thd(this); > #endif > user_connect=(USER_CONN *)0; > - my_hash_init(key_memory_user_var_entry, &user_vars, system_charset_info, > + my_hash_init(key_memory_user_var_entry, &user_vars, > + Lex_ident_user_var::charset_info(), > USER_VARS_HASH_SIZE, 0, 0, (my_hash_get_key) get_var_key, > (my_hash_free_key) free_user_var, HASH_THREAD_SPECIFIC); > - my_hash_init(PSI_INSTRUMENT_ME, &sequences, system_charset_info, > + my_hash_init(PSI_INSTRUMENT_ME, &sequences, > + // QQ: why case insensitive? looks like a bug, can you do a test case for it, please? > + &my_charset_utf8mb3_general1400_as_ci, > SEQUENCES_HASH_SIZE, 0, 0, (my_hash_get_key) > get_sequence_last_key, (my_hash_free_key) free_sequence_last, > HASH_THREAD_SPECIFIC); > @@ -4011,7 +4015,7 @@ Table_ident::to_ident_db_internal_with_error(Query_arena *arena) const > if (is_derived_table()) > { > DBUG_ASSERT(db.str == empty_c_string && db.length == 0); > - return Lex_ident_db(empty_c_string, 0); > + return Lex_ident_db(empty_c_string, (size_t) 0); why? > } > // Normal table or JSON table > return arena->to_ident_db_internal_with_error(db); > diff --git a/sql/sql_class.h b/sql/sql_class.h > index 214118d8431..5685240ceaf 100644 > --- a/sql/sql_class.h > +++ b/sql/sql_class.h > @@ -433,13 +435,14 @@ class Alter_rename_key : public Sql_alloc > class Alter_index_ignorability: public Sql_alloc > { > public: > - Alter_index_ignorability(const char *name, bool is_ignored, bool if_exists) : > + Alter_index_ignorability(const LEX_CSTRING &name, > + bool is_ignored, bool if_exists) : > m_name(name), m_is_ignored(is_ignored), m_if_exists(if_exists) > { > - assert(name != NULL); > + assert(name.str != NULL); DBUG_ASSERT > } > > - const char *name() const { return m_name; } > + const Lex_ident_column &name() const { return m_name; } > bool if_exists() const { return m_if_exists; } > > /* The ignorability after the operation is performed. */ > @@ -7989,42 +7995,24 @@ class Identifier_chain2 > class Database_qualified_name > { > public: > - LEX_CSTRING m_db; > - LEX_CSTRING m_name; > - Database_qualified_name(const LEX_CSTRING *db, const LEX_CSTRING *name) > - :m_db(*db), m_name(*name) > + Lex_ident_db m_db; > + Lex_cstring m_name; // no comparison semantics > + Database_qualified_name() > { } > - Database_qualified_name(const LEX_CSTRING &db, const LEX_CSTRING &name) > + Database_qualified_name(const Lex_ident_db &db, const LEX_CSTRING &name) > :m_db(db), m_name(name) > { } > - Database_qualified_name(const char *db, size_t db_length, > - const char *name, size_t name_length) > - { > - m_db.str= db; > - m_db.length= db_length; > - m_name.str= name; > - m_name.length= name_length; > - } > - > - bool eq(const Database_qualified_name *other) const > + bool eq_routine_name(const Database_qualified_name *other) const eq_func_name, because the comparison semantics comes from Lex_ident_func > { > - CHARSET_INFO *cs= lower_case_table_names ? > - &my_charset_utf8mb3_general_ci : > - &my_charset_utf8mb3_bin; > - return > - m_db.length == other->m_db.length && > - m_name.length == other->m_name.length && > - !cs->strnncoll(m_db.str, m_db.length, > - other->m_db.str, other->m_db.length) && > - !cs->strnncoll(m_name.str, m_name.length, > - other->m_name.str, other->m_name.length); > + return m_db.streq(other->m_db) && no need to take lower_case_table_names into account when comparing db names here? > + Lex_ident_func(m_name).streq(other->m_name); > } > /* > Make copies of "db" and "name" on the memory root in internal format: > - Lower-case "db" if lower-case-table-names==1. > - Preserve "name" as is. > */ > - bool copy_sp_name_internal(MEM_ROOT *mem_root, const LEX_CSTRING &db, > + bool copy_sp_name_internal(MEM_ROOT *mem_root, const Lex_ident_db &db, > const LEX_CSTRING &name); > > // Export db and name as a qualified name string: 'db.name' > diff --git a/sql/sql_connect.cc b/sql/sql_connect.cc > index c5619b28f69..4e10f498e3c 100644 > --- a/sql/sql_connect.cc > +++ b/sql/sql_connect.cc > @@ -509,7 +514,9 @@ extern "C" void free_table_stats(TABLE_STATS* table_stats) > > void init_global_table_stats(void) > { > - my_hash_init(PSI_INSTRUMENT_ME, &global_table_stats, system_charset_info, > + my_hash_init(PSI_INSTRUMENT_ME, &global_table_stats, > + // QQ: why not Lex_ident_table::charset_info() ? just change it > + &my_charset_utf8mb3_general1400_as_ci, > max_connections, 0, 0, (my_hash_get_key) get_key_table_stats, > (my_hash_free_key) free_table_stats, 0); > } > diff --git a/sql/sql_db.cc b/sql/sql_db.cc > index 08441d9f067..51635bdf0ce 100644 > --- a/sql/sql_db.cc > +++ b/sql/sql_db.cc > @@ -98,12 +98,10 @@ typedef struct my_dbopt_st > */ > > static inline bool > -cmp_db_names(LEX_CSTRING *db1_name, const LEX_CSTRING *db2_name) > +cmp_db_names(const Lex_ident_db &db1_name, const Lex_ident_db &db2_name) > { > - return (db1_name->length == db2_name->length && > - (db1_name->length == 0 || can it be used with empty names, really? > - my_strcasecmp(table_alias_charset, > - db1_name->str, db2_name->str) == 0)); > + return (db1_name.length == 0 && db2_name.length == 0) || > + db1_name.streq(db2_name); > } > > #ifdef HAVE_PSI_INTERFACE > @@ -1087,8 +1085,7 @@ mysql_rm_db_internal(THD *thd, const Lex_ident_db &db, bool if_exists, > Disable drop of enabled log tables, must be done before name locking. > This check is only needed if we are dropping the "mysql" database. > */ > - if ((rm_mysql_schema= > - (my_strcasecmp(system_charset_info, MYSQL_SCHEMA_NAME.str, db.str) == 0))) > + if ((rm_mysql_schema= MYSQL_SCHEMA_NAME.streq(db))) // QQ: was a bug here? again, "was" > { > for (table= tables; table; table= table->next_local) > if (check_if_log_table(table, TRUE, "DROP")) > diff --git a/sql/sql_handler.cc b/sql/sql_handler.cc > index 406f67ff955..def1fc44392 100644 > --- a/sql/sql_handler.cc > +++ b/sql/sql_handler.cc > @@ -1080,11 +1079,14 @@ static SQL_HANDLER *mysql_ha_find_match(THD *thd, TABLE_LIST *tables) > { > if (tables->is_anonymous_derived_table()) > continue; > + /* > + TODO: for some reasons the code user case-insensitive comparison. > + Shouldn't it use Lex_ident_db/Lex_ident_table instead, > + to take into account the filesystem case sensitivity? > + */ must be a bug. try to create a test case for it. I think it could be something like (untested) create table t1 ...; create table T1; handler t1 open; handler t1 read first; handler t1 read next; drop table T1; handler t1 read next; > if ((! tables->db.str[0] || > - ! my_strcasecmp(&my_charset_latin1, hash_tables->db.str, > - tables->get_db_name())) && > - ! my_strcasecmp(&my_charset_latin1, hash_tables->table_name.str, > - tables->get_table_name())) > + Lex_ident_ci(hash_tables->db).streq(tables->get_db_name())) && > + Lex_ident_ci(hash_tables->table_name).streq(tables->get_table_name())) > { > /* Link into hash_tables list */ > hash_tables->next= head; > diff --git a/sql/sql_i_s.h b/sql/sql_i_s.h > index 263031ae2c9..127b35f6ab2 100644 > --- a/sql/sql_i_s.h > +++ b/sql/sql_i_s.h > @@ -329,7 +325,7 @@ typedef class Item COND; > > typedef struct st_schema_table > { > - const char *table_name; > + LEX_CSTRING table_name; why LEX_CSTRING? > ST_FIELD_INFO *fields_info; > /* for FLUSH table_name */ > int (*reset_table) (); > diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc > index a84fd29affc..b74ecb51a69 100644 > --- a/sql/sql_lex.cc > +++ b/sql/sql_lex.cc > @@ -9370,8 +9359,8 @@ bool LEX::create_package_finalize(THD *thd, > { > if (name2 && > (name2->m_explicit_name != name->m_explicit_name || > - strcmp(name2->m_db.str, name->m_db.str) || > - !Sp_handler::eq_routine_name(name2->m_name, name->m_name))) > + // QQ: was a bug here? "was" may be it was intentional, looking for an exact match only? > + !name2->eq_routine_name(name))) > { > bool exp= name2->m_explicit_name || name->m_explicit_name; > my_error(ER_END_IDENTIFIER_DOES_NOT_MATCH, MYF(0), > diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc > index 665d2143872..1430aa473af 100644 > --- a/sql/sql_parse.cc > +++ b/sql/sql_parse.cc > @@ -1131,8 +1131,8 @@ static bool wsrep_tables_accessible_when_detached(const TABLE_LIST *tables) > { > for (const TABLE_LIST *table= tables; table; table= table->next_global) I'd personally use const TABLE_LIST *t= tables; ... it's a 3-line loop > { > - LEX_CSTRING db= table->db, tn= table->table_name; > - if (get_table_category(&db, &tn) < TABLE_CATEGORY_INFORMATION) > + if (get_table_category(table->db, > + table->table_name) < TABLE_CATEGORY_INFORMATION) > return false; > } > return tables != NULL; > diff --git a/sql/sql_partition.cc b/sql/sql_partition.cc > index 958c52fd95c..c8d64ea37ff 100644 > --- a/sql/sql_partition.cc > +++ b/sql/sql_partition.cc > @@ -8055,13 +8050,9 @@ void make_used_partitions_str(MEM_ROOT *alloc, > if (parts_str->length()) > parts_str->append(','); > uint index= parts_str->length(); > - parts_str->append(head_pe->partition_name, > - strlen(head_pe->partition_name), > - system_charset_info); > + parts_str->append(head_pe->partition_name, system_charset_info); > parts_str->append('_'); > - parts_str->append(pe->partition_name, > - strlen(pe->partition_name), > - system_charset_info); > + parts_str->append(pe->partition_name, system_charset_info); better pe->partition_name->charset_info() (here and above and below) > used_partitions_list.append_str(alloc, parts_str->ptr() + index); > } > partition_id++; > diff --git a/sql/sql_plugin.cc b/sql/sql_plugin.cc > index 8bab244c709..f335226b9a2 100644 > --- a/sql/sql_plugin.cc > +++ b/sql/sql_plugin.cc > @@ -374,16 +374,16 @@ bool check_valid_path(const char *path, size_t len) > > static void fix_dl_name(MEM_ROOT *root, LEX_CSTRING *dl) > { > - const size_t so_ext_len= sizeof(SO_EXT) - 1; > - if (dl->length < so_ext_len || > - my_strcasecmp(&my_charset_latin1, dl->str + dl->length - so_ext_len, > - SO_EXT)) > + const Lex_ident_plugin so_ext(SO_EXT, sizeof(SO_EXT) - 1); STRING_WITH_LEN > + if (dl->length < so_ext.length || > + !so_ext.streq(Lex_cstring(dl->str + dl->length - so_ext.length, > + so_ext.length))) > { > - char *s= (char*)alloc_root(root, dl->length + so_ext_len + 1); > + char *s= (char*)alloc_root(root, dl->length + so_ext.length + 1); > memcpy(s, dl->str, dl->length); > strcpy(s + dl->length, SO_EXT); > dl->str= s; > - dl->length+= so_ext_len; > + dl->length+= so_ext.length; > } > } > > diff --git a/sql/sql_show.cc b/sql/sql_show.cc > index 1fcafd6ec08..7548ff1ec57 100644 > --- a/sql/sql_show.cc > +++ b/sql/sql_show.cc > @@ -7182,10 +7170,12 @@ static int get_schema_views_record(THD *thd, TABLE_LIST *tables, > Security_context *sctx= thd->security_ctx; > if (!tables->allowed_show) > { > - if (!my_strcasecmp(system_charset_info, tables->definer.user.str, > - sctx->priv_user) && > - !my_strcasecmp(system_charset_info, tables->definer.host.str, > - sctx->priv_host)) > + // QQ: why case insensitive comparision? Same as above? Try a test case and fix if a bug? it's likely create user foo; create user FOO; create view ... definer=foo v1 ... connect(as FOO); select * from information schema.views; > + if (my_charset_utf8mb3_general1400_as_ci.streq( > + tables->definer.user, > + Lex_cstring_strlen(sctx->priv_user)) && > + Lex_ident_host(tables->definer.host). > + streq(Lex_cstring_strlen(sctx->priv_host))) > tables->allowed_show= TRUE; > #ifndef NO_EMBEDDED_ACCESS_CHECKS > else > @@ -7893,8 +7883,7 @@ static int get_schema_partitions_record(THD *thd, TABLE_LIST *tables, > > while ((part_elem= part_it++)) > { > - table->field[3]->store(part_elem->partition_name, > - strlen(part_elem->partition_name), cs); > + table->field[3]->store(part_elem->partition_name, cs); may be part_elem->partition_name->charset_info() ? > table->field[3]->set_notnull(); > /* PARTITION_ORDINAL_POSITION */ > table->field[5]->store((longlong) ++part_pos, TRUE); > diff --git a/sql/sql_trigger.cc b/sql/sql_trigger.cc > index 5304a535ad0..dcba31d06c9 100644 > --- a/sql/sql_trigger.cc > +++ b/sql/sql_trigger.cc > @@ -470,7 +470,7 @@ bool mysql_create_or_drop_trigger(THD *thd, TABLE_LIST *tables, bool create) > /* > We don't allow creating triggers on tables in the 'mysql' schema > */ > - if (create && lex_string_eq(&tables->db, STRING_WITH_LEN("mysql"))) > + if (create && tables->db.streq(MYSQL_SCHEMA_NAME)) // QQ: was a bug here? "was" > { > my_error(ER_NO_TRIGGERS_ON_SYSTEM_SCHEMA, MYF(0)); > DBUG_RETURN(TRUE); > diff --git a/sql/sql_trigger.h b/sql/sql_trigger.h > index 493349afb9d..5648f8f15ff 100644 > --- a/sql/sql_trigger.h > +++ b/sql/sql_trigger.h > @@ -74,8 +74,10 @@ struct st_trg_execution_order > /** > Trigger name referenced in the FOLLOWS/PRECEDES clause of the > CREATE TRIGGER statement. > + Cannot be Lex_ident_trigger, > + as this structure is used in %union in sql_yacc.yy Thanks. I already wrote above "why it's not simply a Lex_ident_trigger. That explains it, deleted my previous comment :) > */ > - LEX_CSTRING anchor_trigger_name; > + LEX_CSTRING anchor_trigger_name; // Used in sql_yacc %union > }; > > > diff --git a/sql/sql_truncate.cc b/sql/sql_truncate.cc > index beeee9da72f..e3efc3122df 100644 > --- a/sql/sql_truncate.cc > +++ b/sql/sql_truncate.cc > @@ -147,14 +147,12 @@ fk_truncate_illegal_if_parent(THD *thd, TABLE *table) > /* Loop over the set of foreign keys for which this table is a parent. */ > while ((fk_info= it++)) > { > - if (lex_string_cmp(system_charset_info, fk_info->referenced_db, > - &table->s->db) || > - lex_string_cmp(system_charset_info, fk_info->referenced_table, > - &table->s->table_name) || > - lex_string_cmp(system_charset_info, fk_info->foreign_db, > - &table->s->db) || > - lex_string_cmp(system_charset_info, fk_info->foreign_table, > - &table->s->table_name)) > + // QQ: why db and table don't use table_alias_charset for comparison? Same as above? Try a test case and fix if a bug? test looks fairly straightforward here too > + if (!Lex_ident_ci(*fk_info->referenced_db).streq(table->s->db) || > + !Lex_ident_ci(*fk_info->referenced_table). > + streq(table->s->table_name) || > + !Lex_ident_ci(*fk_info->foreign_db).streq(table->s->db) || > + !Lex_ident_ci(*fk_info->foreign_table).streq(table->s->table_name)) > break; > } > > diff --git a/sql/sql_view.cc b/sql/sql_view.cc > index 10588b54fa5..751373b4571 100644 > --- a/sql/sql_view.cc > +++ b/sql/sql_view.cc > @@ -1347,12 +1347,9 @@ bool mysql_make_view(THD *thd, TABLE_SHARE *share, TABLE_LIST *table, > precedent; > precedent= precedent->referencing_view) > { > - if (precedent->view_name.length == table->table_name.length && > - precedent->view_db.length == table->db.length && > - my_strcasecmp(system_charset_info, > - precedent->view_name.str, table->table_name.str) == 0 && > - my_strcasecmp(system_charset_info, > - precedent->view_db.str, table->db.str) == 0) > + // QQ: was a bug here? "was" > + if (precedent->view_name.streq(table->table_name) && > + precedent->view_db.streq(table->db)) > { > my_error(ER_VIEW_RECURSIVE, MYF(0), > top_view->view_db.str, top_view->view_name.str); > diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy > index fcfe490c035..d01c195cb8a 100644 > --- a/sql/sql_yacc.yy > +++ b/sql/sql_yacc.yy > @@ -15676,7 +15680,8 @@ user_maybe_role: > It's OK to use in-place lowercase as long as > the character set is utf8. > */ > - my_casedn_str(system_charset_info, (char*) $$->host.str); > + $$->host.length= my_casedn_str(system_charset_info, > + (char*) $$->host.str); I thought my_casedn_str() changes were in the different commit? > } > else > { > diff --git a/sql/structs.h b/sql/structs.h > index 75bdc9e276b..d349ab72970 100644 > --- a/sql/structs.h > +++ b/sql/structs.h > @@ -321,11 +322,25 @@ typedef struct user_conn { > uint conn_per_hour, updates, questions; > /* Maximum amount of resources which account is allowed to consume. */ > USER_RESOURCES user_resources; > + > + /* > + The CHARSET_INFO used for hashes to compare the entire 'user\0hash' key. > + QQ: perhaps the user should be compared case sensitively, > + while host host should be comparad case insensitively. correct > + */ > + static CHARSET_INFO *user_host_key_charset_info_for_hash() > + { > + return &my_charset_utf8mb3_general1400_as_ci; > + } > } USER_CONN; > > typedef struct st_user_stats > { > char user[MY_MAX(USERNAME_LENGTH, LIST_PROCESS_HOST_LEN) + 1]; > + static CHARSET_INFO *user_key_charset_info_for_hash() > + { > + return &my_charset_utf8mb3_general1400_as_ci; > + } > // Account name the user is mapped to when this is a user from mapped_user. > // Otherwise, the same value as user. > char priv_user[MY_MAX(USERNAME_LENGTH, LIST_PROCESS_HOST_LEN) + 1]; > diff --git a/sql/table.cc b/sql/table.cc > index 8bc16753e68..d9bc5fabb4f 100644 > --- a/sql/table.cc > +++ b/sql/table.cc > @@ -88,23 +88,34 @@ struct extra2_fields > static Virtual_column_info * unpack_vcol_info_from_frm(THD *, > TABLE *, String *, Virtual_column_info **, bool *); > > +/* > + Lex_ident_db does not have operator""_Lex_ident_db, > + because its constructor contains DBUG_SLOW_ASSERT > + and therefore it's not a constexpr constructor. > + So let's initialize a number of Lex_ident_db constants > + using operator""_Lex_cstring. > +*/ > + > /* INFORMATION_SCHEMA name */ > -LEX_CSTRING INFORMATION_SCHEMA_NAME= {STRING_WITH_LEN("information_schema")}; > +Lex_ident_db > + INFORMATION_SCHEMA_NAME= Lex_ident_db("information_schema"_Lex_cstring); don't think so. information_schema is case insensitive, even if fs is case sensitivity > > /* PERFORMANCE_SCHEMA name */ > -LEX_CSTRING PERFORMANCE_SCHEMA_DB_NAME= {STRING_WITH_LEN("performance_schema")}; > +Lex_ident_db > + PERFORMANCE_SCHEMA_DB_NAME= Lex_ident_db("performance_schema"_Lex_cstring); same > > /* MYSQL_SCHEMA name */ > -LEX_CSTRING MYSQL_SCHEMA_NAME= {STRING_WITH_LEN("mysql")}; > +Lex_ident_db > + MYSQL_SCHEMA_NAME= Lex_ident_db("mysql"_Lex_cstring); this uses fs case sensitivity, correct > > /* GENERAL_LOG name */ > -LEX_CSTRING GENERAL_LOG_NAME= {STRING_WITH_LEN("general_log")}; > +Lex_ident_table GENERAL_LOG_NAME= "general_log"_Lex_ident_table; > > /* SLOW_LOG name */ > -LEX_CSTRING SLOW_LOG_NAME= {STRING_WITH_LEN("slow_log")}; > +Lex_ident_table SLOW_LOG_NAME= "slow_log"_Lex_ident_table; > > -LEX_CSTRING TRANSACTION_REG_NAME= {STRING_WITH_LEN("transaction_registry")}; > -LEX_CSTRING MYSQL_PROC_NAME= {STRING_WITH_LEN("proc")}; > +Lex_ident_table TRANSACTION_REG_NAME= "transaction_registry"_Lex_ident_table; > +Lex_ident_table MYSQL_PROC_NAME= "proc"_Lex_ident_table; > > /* > Keyword added as a prefix when parsing the defining expression for a > @@ -280,42 +291,38 @@ const char *fn_frm_ext(const char *name) > } > > > -TABLE_CATEGORY get_table_category(const LEX_CSTRING *db, > - const LEX_CSTRING *name) > +TABLE_CATEGORY get_table_category(const Lex_ident_db &db, > + const Lex_ident_table &name) > { > - DBUG_ASSERT(db != NULL); > - DBUG_ASSERT(name != NULL); > - > #ifdef WITH_WSREP > - if (db->str && > - my_strcasecmp(system_charset_info, db->str, WSREP_SCHEMA) == 0) > + if (db.str && db.streq(MYSQL_SCHEMA_NAME)) //QQ: was a bug here? "was" > { > - if ((my_strcasecmp(system_charset_info, name->str, WSREP_STREAMING_TABLE) == 0 || > - my_strcasecmp(system_charset_info, name->str, WSREP_CLUSTER_TABLE) == 0 || > - my_strcasecmp(system_charset_info, name->str, WSREP_MEMBERS_TABLE) == 0)) > + if (name.streq(Lex_ident_table{STRING_WITH_LEN(WSREP_STREAMING_TABLE)}) || > + name.streq(Lex_ident_table{STRING_WITH_LEN(WSREP_CLUSTER_TABLE)}) || > + name.streq(Lex_ident_table{STRING_WITH_LEN(WSREP_MEMBERS_TABLE)})) > { > return TABLE_CATEGORY_INFORMATION; > } > } > #endif /* WITH_WSREP */ > - if (is_infoschema_db(db)) > + if (is_infoschema_db(&db)) > return TABLE_CATEGORY_INFORMATION; > > - if (is_perfschema_db(db)) > + if (is_perfschema_db(&db)) > return TABLE_CATEGORY_PERFORMANCE; > > - if (lex_string_eq(&MYSQL_SCHEMA_NAME, db)) > + if (db.streq(MYSQL_SCHEMA_NAME)) // QQ: was a bug here? "was" > { > - if (is_system_table_name(name->str, name->length)) > + if (is_system_table_name(name.str, name.length)) > return TABLE_CATEGORY_SYSTEM; > > - if (lex_string_eq(&GENERAL_LOG_NAME, name)) > + if (name.streq(GENERAL_LOG_NAME)) // QQ: was bug here? "was" > return TABLE_CATEGORY_LOG; > > - if (lex_string_eq(&SLOW_LOG_NAME, name)) > + if (name.streq(SLOW_LOG_NAME)) // QQ: was a bug here? "was" > return TABLE_CATEGORY_LOG; > > - if (lex_string_eq(&TRANSACTION_REG_NAME, name)) > + if (name.streq(TRANSACTION_REG_NAME)) // QQ: was a bug here? "was" > return TABLE_CATEGORY_LOG; > } > > diff --git a/sql/table.h b/sql/table.h > index 35be3bd4b2d..fe65025478d 100644 > --- a/sql/table.h > +++ b/sql/table.h > @@ -3402,27 +3409,27 @@ static inline int set_zone(int nr,int min_zone,int max_zone) > } > > /* performance schema */ > -extern LEX_CSTRING PERFORMANCE_SCHEMA_DB_NAME; > +extern Lex_ident_db PERFORMANCE_SCHEMA_DB_NAME; > > -extern LEX_CSTRING GENERAL_LOG_NAME; > -extern LEX_CSTRING SLOW_LOG_NAME; > -extern LEX_CSTRING TRANSACTION_REG_NAME; > +extern Lex_ident_table GENERAL_LOG_NAME; > +extern Lex_ident_table SLOW_LOG_NAME; > +extern Lex_ident_table TRANSACTION_REG_NAME; > > /* information schema */ > -extern LEX_CSTRING INFORMATION_SCHEMA_NAME; > -extern LEX_CSTRING MYSQL_SCHEMA_NAME; > +extern Lex_ident_db INFORMATION_SCHEMA_NAME; > +extern Lex_ident_db MYSQL_SCHEMA_NAME; > > /* table names */ > -extern LEX_CSTRING MYSQL_PROC_NAME; > +extern Lex_ident_table MYSQL_PROC_NAME; > > inline bool is_infoschema_db(const LEX_CSTRING *name) > { > - return lex_string_eq(&INFORMATION_SCHEMA_NAME, name); > + return lex_string_eq(&INFORMATION_SCHEMA_NAME, name); // QQ: use Lex_ident_ci ? yes > } > > inline bool is_perfschema_db(const LEX_CSTRING *name) > { > - return lex_string_eq(&PERFORMANCE_SCHEMA_DB_NAME, name); > + return lex_string_eq(&PERFORMANCE_SCHEMA_DB_NAME, name); // QQ: use Lex_ident_ci? yes > } > > inline void mark_as_null_row(TABLE *table) > diff --git a/storage/blackhole/ha_blackhole.cc b/storage/blackhole/ha_blackhole.cc > index 343f3c70286..ce48c95f837 100644 > --- a/storage/blackhole/ha_blackhole.cc > +++ b/storage/blackhole/ha_blackhole.cc > @@ -416,7 +416,9 @@ static int blackhole_init(void *p) > mysql_mutex_init(bh_key_mutex_blackhole, > &blackhole_mutex, MY_MUTEX_INIT_FAST); > (void) my_hash_init(PSI_INSTRUMENT_ME, &blackhole_open_tables, > - system_charset_info, 32, 0, 0, > + // QQ: was a bug here? "was" > + Lex_ident_table::charset_info(), > + 32, 0, 0, > (my_hash_get_key) blackhole_get_key, > (my_hash_free_key) blackhole_free_key, 0); > > diff --git a/storage/csv/ha_tina.cc b/storage/csv/ha_tina.cc > index e705ff0e7c0..9fc0bcf604b 100644 > --- a/storage/csv/ha_tina.cc > +++ b/storage/csv/ha_tina.cc > @@ -184,7 +184,9 @@ static int tina_init_func(void *p) > tina_hton= (handlerton *)p; > mysql_mutex_init(csv_key_mutex_tina, &tina_mutex, MY_MUTEX_INIT_FAST); > (void) my_hash_init(csv_key_memory_tina_share, &tina_open_tables, > - system_charset_info, 32, 0, 0, (my_hash_get_key) > + // QQ: was a bug here? "was" > + table_alias_charset, > + 32, 0, 0, (my_hash_get_key) > tina_get_key, 0, 0); > tina_hton->db_type= DB_TYPE_CSV_DB; > tina_hton->create= tina_create_handler; > diff --git a/storage/innobase/dict/dict0dict.cc b/storage/innobase/dict/dict0dict.cc > index 5545727b015..231bcc1a132 100644 > --- a/storage/innobase/dict/dict0dict.cc > +++ b/storage/innobase/dict/dict0dict.cc > @@ -284,27 +284,26 @@ otherwise table->n_def */ > ulint > dict_table_has_column( > const dict_table_t* table, > - const char* col_name, > + const LEX_CSTRING &col_name, looks ok to me, but to avoid surprises Marko should review it too > ulint col_nr) > { > ulint col_max = table->n_def; > > ut_ad(table); > - ut_ad(col_name); > + ut_ad(col_name.str); > ut_ad(table->magic_n == DICT_TABLE_MAGIC_N); > > if (col_nr < col_max > - && innobase_strcasecmp( > - col_name, dict_table_get_col_name(table, col_nr)) == 0) { > + && Lex_ident_column(col_name). > + streq(dict_table_get_col_name_ls(table, col_nr))) { > return(col_nr); > } > > /** The order of column may changed, check it with other columns */ > for (ulint i = 0; i < col_max; i++) { > if (i != col_nr > - && innobase_strcasecmp( > - col_name, dict_table_get_col_name(table, i)) == 0) { > - > + && Lex_ident_column(col_name). > + streq(dict_table_get_col_name_ls(table, i))) { > return(i); > } > } > diff --git a/storage/mroonga/ha_mroonga.cpp b/storage/mroonga/ha_mroonga.cpp > index 44fd09e74ed..71784dad475 100644 > --- a/storage/mroonga/ha_mroonga.cpp > +++ b/storage/mroonga/ha_mroonga.cpp > @@ -1936,7 +1936,10 @@ static int mrn_init(void *p) > MY_MUTEX_INIT_FAST) != 0)) { > goto err_allocated_thds_mutex_init; > } > - if (mrn_my_hash_init(&mrn_allocated_thds, system_charset_info, 32, 0, 0, > + if (mrn_my_hash_init(&mrn_allocated_thds, > + // QQ: was a bug here? "was" > + &my_charset_bin, > + 32, 0, 0, > mrn_allocated_thds_get_key, 0, 0)) { > goto error_allocated_thds_hash_init; > } > @@ -1945,7 +1948,10 @@ static int mrn_init(void *p) > MY_MUTEX_INIT_FAST) != 0)) { > goto err_allocated_open_tables_mutex_init; > } > - if (mrn_my_hash_init(&mrn_open_tables, system_charset_info, 32, 0, 0, > + if (mrn_my_hash_init(&mrn_open_tables, > + // QQ: was a bug here? "was" > + Lex_ident_table::charset_info(), > + 32, 0, 0, > mrn_open_tables_get_key, 0, 0)) { > goto error_allocated_open_tables_hash_init; > } > @@ -1954,7 +1960,10 @@ static int mrn_init(void *p) > MY_MUTEX_INIT_FAST) != 0)) { > goto error_allocated_long_term_share_mutex_init; > } > - if (mrn_my_hash_init(&mrn_long_term_share, system_charset_info, 32, 0, 0, > + if (mrn_my_hash_init(&mrn_long_term_share, > + // QQ: was a bug here? "was" > + Lex_ident_table::charset_info(), > + 32, 0, 0, > mrn_long_term_share_get_key, 0, 0)) { > goto error_allocated_long_term_share_hash_init; > } > diff --git a/storage/perfschema/pfs_engine_table.h b/storage/perfschema/pfs_engine_table.h > index 1ef1e0282de..b4f4c9f0acc 100644 > --- a/storage/perfschema/pfs_engine_table.h > +++ b/storage/perfschema/pfs_engine_table.h > @@ -25,6 +25,22 @@ > > #include "table.h" > #include "sql_acl.h" > + > +/* > + The performance schema is implemented as a storage engine, in memory. > + The current storage engine interface exposed by the server, > + and in particular handlerton::discover, uses 'FRM' files to describe a > + table structure, which are later stored on disk, by the server, > + in ha_create_table_from_engine(). > + Because the table metadata is stored on disk, the table naming rules > + used by the performance schema then have to comply with the constraints > + imposed by the disk storage, and in particular with lower_case_table_names. > +*/ > + > +using PFS_ident_db= Lex_ident_db; > +using PFS_ident_table = Lex_ident_table; No, table metadata for performance schema are never stored on disk. let's use case insensitive comparison here, if possible. > + > + > /** > @file storage/perfschema/pfs_engine_table.h > Performance schema tables (declarations). Regards, Sergei Chief Architect, MariaDB Server and security(a)mariadb.org

2 5

Re: 9d6de9212d5: MDEV-29095 REGEXP_REPLACE treats empty strings different than REPLACE in ORACLE mode
by Sergei Golubchik 16 Jan '24

16 Jan '24

Hi, Alexander, On Jan 10, Alexander Barkov wrote: > revision-id: 9d6de9212d5 (mariadb-10.4.32-45-g9d6de9212d5) > parent(s): bdfd93d30c1 > author: Alexander Barkov > committer: Alexander Barkov > timestamp: 2023-11-24 13:23:56 +0400 > message: > > MDEV-29095 REGEXP_REPLACE treats empty strings different than REPLACE in ORACLE mode > > Turning REGEXP_REPLACE into two schema-qualified functions: > - mariadb_schema.regexp_replace() > - oracle_schema.regexp_replace() > > Fixing oracle_schema.regexp_replace(subj,pattern,replacement) to treat > NULL in "replacement" as an empty string. > > Adding new classes implementing oracle_schema.regexp_replace(): > - Item_func_regexp_replace_oracle > - Create_func_regexp_replace_oracle > > diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc > index 92d5e196da4..b688ba97d3e 100644 > --- a/sql/item_strfunc.cc > +++ b/sql/item_strfunc.cc > @@ -1385,20 +1385,22 @@ bool Item_func_regexp_replace::append_replacement(String *str, > } > > > -String *Item_func_regexp_replace::val_str(String *str) > +String *Item_func_regexp_replace::val_str_internal(String *str, > + bool null_to_empty) > { > DBUG_ASSERT(fixed == 1); > char buff0[MAX_FIELD_WIDTH]; > char buff2[MAX_FIELD_WIDTH]; > String tmp0(buff0,sizeof(buff0),&my_charset_bin); > String tmp2(buff2,sizeof(buff2),&my_charset_bin); > - String *source= args[0]->val_str(&tmp0); > - String *replace= args[2]->val_str(&tmp2); > + String *source, *replace; > LEX_CSTRING src, rpl; > int startoffset= 0; > > - if ((null_value= (args[0]->null_value || args[2]->null_value || > - re.recompile(args[1])))) > + if ((null_value= > + (!(source= args[0]->val_str(&tmp0)) || > + !(replace= args[2]->val_str_null_to_empty(&tmp2, null_to_empty)) || why are you fixing it differently from Item_func_replace? If you think this approach is better then, please, change Item_func_replace to use it too, in a followup commit. > + re.recompile(args[1])))) > return (String *) 0; > > if (!(source= re.convert_if_needed(source, &re.subject_converter)) || > diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h > index 826c7f784af..e014cc5fcbc 100644 > --- a/sql/item_strfunc.h > +++ b/sql/item_strfunc.h > @@ -412,11 +420,34 @@ class Item_func_regexp_replace :public Item_str_func > re.cleanup(); > DBUG_VOID_RETURN; > } > - String *val_str(String *str); > + String *val_str(String *str) > + { > + return val_str_internal(str, false); > + } > bool fix_fields(THD *thd, Item **ref); > bool fix_length_and_dec(); > const char *func_name() const { return "regexp_replace"; } > - Item *get_copy(THD *thd) { return 0;} > + Item *get_copy(THD *thd) { return 0;} // QQ: why? you could've checked the history in git. it was commit 343bcb152f8 Author: Igor Babaev <igor(a)askmonty.org> Date: Sun Nov 5 22:52:41 2017 -0800 Fixed mdev-14237 Server crash on query with regexp_substr It's better to prohibit pushdown of conditions that involve regexp_substr() and regexp_replace() into materialized derived tables / views until proper implementations of the get_copy() virtual method are provided for those functions. and I suspect the reason is Regexp_processor_pcre inside regexp Items. > +}; > + > + > +class Item_func_regexp_replace_oracle: public Item_func_regexp_replace > +{ > +public: > + Item_func_regexp_replace_oracle(THD *thd, Item *a, Item *b, Item *c) > + :Item_func_regexp_replace(thd, a, b, c) > + {} > + const Schema *schema() const { return &oracle_schema_ref; } > + bool fix_length_and_dec() > + { > + bool rc= Item_func_regexp_replace::fix_length_and_dec(); > + maybe_null= true; // Empty result is converted to NULL > + return rc; > + } > + String *val_str(String *str) > + { > + return val_str_internal(str, true); > + } > }; Regards, Sergei Chief Architect, MariaDB Server and security(a)mariadb.org

2 1

Re: 22e2f082400: MDEV-25370 Update for portion changes autoincrement key in bi-temp table
by Sergei Golubchik 12 Jan '24

12 Jan '24

Hi, Nikita, On Jan 06, Nikita Malyavin wrote: > revision-id: 22e2f082400 (mariadb-10.5.23-39-g22e2f082400) > parent(s): e472b682e06 > author: Nikita Malyavin > committer: Nikita Malyavin > timestamp: 2023-12-20 02:46:09 +0100 > message: > > MDEV-25370 Update for portion changes autoincrement key in bi-temp table > > According to the standard, the autoincrement column (i.e. *identity > column*) should be advanced each insert implicitly made by > UPDATE/DELETE ... FOR PORTION. When you refer to the standard, specify the exact reference so that someone could verify it. E.g. as I've commented in MDEV, "SQL:2016, Part 2, 15.13 Effect of replacing rows in base tables, paragraph 10) b) i)" Also, the standard doesn't have autoincrement, it'd be better to say "According to the standard, the identity column (which autoincrement is a functional analog of) should be advanced...." > This is very unconvenient use in several notable cases. Concider a > WITHOUT OVERLAPS key with an autoinc column: > id int auto_increment, unique(id, p without overlaps) > > An update or delete with FOR PORTION creates a sense that id will > remain unchanged in such case. > > This commit makes an exception the autoinc columns that are part of > WITHOUT OVERLAPS keys and infers the following rule for the newly > inserted rows: Better to say here not that we're making an exception and violating the standard (because we are not), but that in the standard IDENTITY uses its own independent sequence generator, which knows nothing about periods. While autoincrement always requires an index (that is, our "identity" column is a pair {autoincrement, index}, not autoincrement alone), and the index can be declared WITHOUT OVERLAPS, so our "identity" column is period-aware. This is an extension of the standard, and we can freely define how it behaves in the cases not covered by the standard, that is in the WITHOUT OVERLAPS case. > ===== > Let V_j a set of values for currently updating/deleting row. > Let VI_j a set of values to be inserted. > * Case: > (a) if V_i is an identity column that is also a part of a unique constraint > that includes <without overlap specification>, then let VI_i be V_i > (b) otherwise, let VI_i be the value deduced as described by the rules of > ISO/IEC 9075-2, clauses 15.7 Effect of deleting rows from base tables > and 15.13 Effect of replacing rows in base tables. > ===== That's confusing, I'm sure that anyone who doesn't remember the corresponding part of the sql standard will think it's a direct quote from it. You've imitated the style rather convincingly :) It's also rather unnecessary, we don't have identity columns, so nobody cares how they should behave in this case. Perhaps it'd be better if you simply write that if the key, that defines autoincrement values, is declared WITHOUT OVERLAPS, then new rows created by UPDATE/DELETE FOR PORTION OF will use old autoincrement values, as they belong to non-overlapping ranges. But INSERT will generate a new autoincrement value, it will not try to find the smallest value in the overlapping ranges. > Note that this also infers that if an identity column is not a part of > any unique constraint that includes <without overlap specification>, then > its value will be DEFAULT and, that is, auto-incremented. > > Apart from WITHOUT OVERLAPS there is also another notable case, referred > by the reporter - a unique key that has an autoincrement column and a field > from the period specification: > id int auto_increment, unique(id, s), period for p(s, e) > > for this case, no exception is made, and the autoincrementing rules will be > proceeded accordung to the standard (i.e. the value will be advanced on > implicit inserts). > > diff --git a/mysql-test/suite/period/r/overlaps.result b/mysql-test/suite/period/r/overlaps.result > --- a/mysql-test/suite/period/r/overlaps.result > +++ b/mysql-test/suite/period/r/overlaps.result > @@ -449,3 +449,86 @@ VALUES > ('2000-01-01 00:00:00.000000', '2001-01-01 00:00:00.000000', 'abc'); > ERROR 23000: Duplicate entry 'abc-2001-01-01 00:00:00.000000-2000-01-01 00:00:00.000000' for key 'index_name' > DROP TABLE t1; > +create or replace table cars(id int auto_increment, > +price int, s date, e date, > +period for p(s,e), > +primary key(id, p without overlaps)); > +insert into cars(price, s, e) values (1000, '2018-01-01', '2020-01-01'); > +select * from cars; > +id price s e > +1 1000 2018-01-01 2020-01-01 > +update cars for portion of p from '2019-01-01' to '2019-12-01' set price= 1100; > +select * from cars; > +id price s e > +1 1000 2018-01-01 2019-01-01 > +1 1000 2019-12-01 2020-01-01 > +1 1100 2019-01-01 2019-12-01 > +delete from cars for portion of p from '2019-12-10' to '2019-12-20'; > +select * from cars; > +id price s e > +1 1000 2018-01-01 2019-01-01 > +1 1000 2019-12-01 2019-12-10 > +1 1000 2019-12-20 2020-01-01 > +1 1100 2019-01-01 2019-12-01 ok > +# AUTO_INCREMENT field is separate from WITHOUT OVERLAPS > +create or replace table cars(id int primary key auto_increment, > +car_id int, > +price int, s date, e date, > +period for p(s,e), > +unique(car_id, p without overlaps)); > +insert cars(car_id, price, s, e) values (1, 1000, '2018-01-01', '2020-01-01'); > +select * from cars; > +id car_id price s e > +1 1 1000 2018-01-01 2020-01-01 > +update cars for portion of p from '2019-01-01' to '2019-12-01' set price= 1100; > +select * from cars; > +id car_id price s e > +1 1 1100 2019-01-01 2019-12-01 > +2 1 1000 2018-01-01 2019-01-01 > +3 1 1000 2019-12-01 2020-01-01 > +delete from cars for portion of p from '2019-12-10' to '2019-12-20'; > +select * from cars; > +id car_id price s e > +1 1 1100 2019-01-01 2019-12-01 > +2 1 1000 2018-01-01 2019-01-01 > +4 1 1000 2019-12-01 2019-12-10 > +5 1 1000 2019-12-20 2020-01-01 right > +# AUTO_INCREMENT field is both standalone and in WITHOUT OVERLAPS > +create or replace table cars(id int primary key auto_increment, > +price int, s date, e date, > +period for p(s,e), > +unique(id, p without overlaps)); > +insert cars(price, s, e) values (1000, '2018-01-01', '2020-01-01'); > +select * from cars; > +id price s e > +1 1000 2018-01-01 2020-01-01 > +update cars for portion of p from '2019-01-01' to '2019-12-01' set price= 1100; > +ERROR 23000: Duplicate entry '1' for key 'PRIMARY' uhm, I don't know. I'd expect that here PRIMARY would define autoincrement values. > +truncate cars; > +insert cars(price, s, e) values (1000, '2018-01-01', '2020-01-01'); > +delete from cars for portion of p from '2019-12-10' to '2019-12-20'; > +ERROR 23000: Duplicate entry '1' for key 'PRIMARY' > +# AUTO_INCREMENT field is non-unique not sure here. I think here unique should define autoincrement values. That is, in both cases, the most restrictive index should define. > +create or replace table cars(id int auto_increment, key(id), > +car_id int, > +price int, s date, e date, > +period for p(s,e), > +unique(car_id, p without overlaps)); > +insert cars(car_id, price, s, e) values (1, 1000, '2018-01-01', '2020-01-01'); > +select * from cars; > +id car_id price s e > +1 1 1000 2018-01-01 2020-01-01 > +update cars for portion of p from '2019-01-01' to '2019-12-01' set price= 1100; > +select * from cars; > +id car_id price s e > +1 1 1100 2019-01-01 2019-12-01 > +2 1 1000 2018-01-01 2019-01-01 > +3 1 1000 2019-12-01 2020-01-01 > +delete from cars for portion of p from '2019-12-10' to '2019-12-20'; > +select * from cars; > +id car_id price s e > +1 1 1100 2019-01-01 2019-12-01 > +2 1 1000 2018-01-01 2019-01-01 > +4 1 1000 2019-12-01 2019-12-10 > +5 1 1000 2019-12-20 2020-01-01 please also add test for INSERT. Just add a second insert like insert cars(price, s, e) values (1000, '2021-01-01', '2022-01-01'); to show that id will *not* be 1 here, even though 1 would not conflict with anything in the specified date range. Simply to have the expected behavior recorded as a test result. > +drop table cars; > diff --git a/sql/table.cc b/sql/table.cc > --- a/sql/table.cc > +++ b/sql/table.cc > @@ -8917,6 +8916,21 @@ int TABLE::update_generated_fields() > return res; > } > > +void TABLE::period_prepare_autoinc() > +{ > + if (!found_next_number_field) > + return; > + > + key_map::Iterator it(found_next_number_field->part_of_key_not_clustered); > + for (uint i; (i= it++) != key_map::Iterator::BITMAP_END;) > + { > + KEY &key= key_info[i]; > + if (key.without_overlaps) > + return; > + } No, I don't think you need to check *all* indexes that the field is part of. I believe you should only check the "main" index, the one that defines autoincrement field behavior. That is only if (key_info[s->next_number_index].without_overlaps) return; > + next_number_field= found_next_number_field; > +} > + > int TABLE::period_make_insert(Item *src, Field *dst) > { > THD *thd= in_use; Regards, Sergei Chief Architect, MariaDB Server and security(a)mariadb.org

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Re: 6835d2ce268: MDEV-28649 json_array(false) in the definition of view return 0 instead of "true".
by Sergei Golubchik 12 Jan '24

12 Jan '24

Hi, Alexey, On Jan 12, Alexey Botchkov wrote: > revision-id: 6835d2ce268 (mariadb-10.4.32-116-g6835d2ce268) > parent(s): fbe604d8839 > author: Alexey Botchkov > committer: Alexey Botchkov > timestamp: 2023-12-15 00:56:20 +0400 > message: > > MDEV-28649 json_array(false) in the definition of view return 0 instead of "true". > > The 'temporary-only Field_bool introduced'; Why did you need a new Field and to change Type_handler_bool from long to tiny? On the first glance it seems that a dedicated Item_bool::print() should've been enough. Regards, Sergei Chief Architect, MariaDB Server and security(a)mariadb.org

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Re: 424ee6eac78: MDEV-32837 long unique does not work like unique key when using replace
by Sergei Golubchik 11 Jan '24

11 Jan '24

Hi, Alexander, On Jan 11, Alexander Barkov wrote: > revision-id: 424ee6eac78 (mariadb-10.5.23-57-g424ee6eac78) > parent(s): c9902a20b3a > author: Alexander Barkov > committer: Alexander Barkov > timestamp: 2024-01-10 15:35:25 +0400 > message: > > MDEV-32837 long unique does not work like unique key when using replace > > diff --git a/sql/sql_insert.cc b/sql/sql_insert.cc > index ec9e379768f..edc2be207f3 100644 > --- a/sql/sql_insert.cc > +++ b/sql/sql_insert.cc > @@ -2065,7 +2065,8 @@ int write_record(THD *thd, TABLE *table, COPY_INFO *info, select_result *sink) > we just should not expose this fact to users by invoking > ON UPDATE triggers. > */ > - if (last_uniq_key(table,key_nr) && > + if ((!table->s->long_unique_table || table->versioned()) && > + last_uniq_key(table,key_nr) && > !table->file->referenced_by_foreign_key() && > (!table->triggers || !table->triggers->has_delete_triggers())) > { 1. why table->versioned() ? 2. use show status in your test for handler_update/delete to see what REPLACE actually did 3. technically, you can keep the optimization if the long unique is the last *and there are no in-engine uniques*, this can be checked with && !(table->key_info->flags & HA_NOSAME) 4. but here's the problem that last_uniq_key() doesn't see long uniques, so it'll treat every one of them as the last. So it should be something like bool is_long_unique= table->s->key_info[key_nr].flags & HA_UNIQUE_HASH; if ((is_long_unique ? last_uniq_key(table, table->s->key_info, key_nr) && !(table->key_info->flags & HA_NOSAME) : last_uniq_key(table, table->key_info, key_nr)) && !table->file->referenced_by_foreign_key() && (!table->triggers || !table->triggers->has_delete_triggers())) I suspect this will correctly use the UPDATE optimization in all cases (only long unique / mix of uniques)x(last / not last key conflicting) Regards, Sergei Chief Architect, MariaDB Server and security(a)mariadb.org

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