March 2017 - developers - lists.mariadb.org

[Maria-developers] Windows line endings in MariaDB sources again (
by Otto Kekäläinen 24 Jul '19

24 Jul '19

Hello! While trying to release 10.0.26 for Debian and Ubuntu I noticed git chokes again on Windows line endings. As our .gitattributes states that by default git should clean up the line endings, why do we keep getting new Windows line endings in new code? mariadb-10.0$ cat .gitattributes # Set the default behavior, in case people don't have core.autocrlf set. * text=auto ... storage/connect/mysql-test/connect/std_data/*.txt -text mariadb-10.0.26$ find . | xargs file | grep CRLF ./storage/connect/mysql-test/connect/std_data/boyswin.txt: ASCII text, with CRLF line terminators ./storage/connect/mysql-test/connect/std_data/expenses.txt: ASCII text, with CRLF line terminators ./storage/connect/mysql-test/connect/std_data/emp.txt: ASCII text, with CRLF line terminators ./mysql-test/std_data/loaddata7.dat: ASCII text, with CRLF line terminators ./mysql-test/r/loadxml.result: ASCII text, with CRLF, LF line terminators ./mysql-test/r/perror-win.result: ASCII text, with CRLF, LF line terminators ./mysql-test/r/mysql_binary_mode.result: ASCII English text, with CRLF, LF line terminators ./mysql-test/r/func_regexp_pcre.result: UTF-8 Unicode C++ program text, with CRLF, CR, LF line terminators ./pcre/testdata/grepoutputN: ASCII text, with CRLF, CR, LF line terminators ./pcre/testdata/greppatN4: ASCII text, with CRLF line terminators This leads for me to: dpkg-source: info: building mariadb-10.0 using existing ./mariadb-10.0_10.0.26.orig.tar.gz dpkg-source: info: local changes detected, the modified files are: mariadb-10.0/storage/connect/mysql-test/connect/std_data/boyswin.txt mariadb-10.0/storage/connect/mysql-test/connect/std_data/emp.txt mariadb-10.0/storage/connect/mysql-test/connect/std_data/expenses.txt dpkg-source: error: aborting due to unexpected upstream changes, see /tmp/mariadb-10.0_10.0.26-1.diff.Yzwwhw Which means I have to do extra work with importing the upstream sources.. - Otto

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Re: [Maria-developers] Mdev-10664 Add statuses about optimistic parallel replication stalls.
by Sachin Setiya 19 Apr '18

19 Apr '18

Hi Kristian! Sorry for late reply , I was on vacations. On Tue, Jan 10, 2017 at 7:31 PM, Kristian Nielsen <knielsen(a)knielsen-hq.org> wrote: > Sachin Setiya <sachin.setiya(a)mariadb.com> writes: > > >> Right, but you still need _some_ way to synchronise multiple threads > > > I used atomic builtins my_atomic_add64_explicit. > > That seems fine (but see comment below). > > > Documentation:- > > > > Slave_DDL_Events:- > > > > Description: Number of DDL statements slave have executed in > > replication channel X. > > Scope: Per Replication Channel > > Data Type: numeric > > Introduced: MariaDB 10.1 > > > > Slave_Non_Transactional_Events:- > > > > Description: Number of Non Transactional "no idea what should be the > > next word " slave have executed in replication channel X. > > Scope: Per Replication Channel > > Data Type: numeric > > Introduced: MariaDB 10.1 > > I checked, the term "event group" is used already multiple places in the > documentation, so I think it can be used here also. An event group can be a > transaction (possibly with multiple transactional DML statements), or a DDL > or non-transactional statement. > > What you are doing is introducing status variables to help understand > optimistic (and aggressive) parallel replication modes. > > In optimistic parallel replication, a non-transactional event group is not > safe to run in parallel with other non-transactional events. So that event > is made to wait for all prior event groups to reach commit state, before > being allowed to execute. However, other transactional events are not > delayed by the non-transactional event group. > > Slave_Non_Transactional_Events counts the occurences of this. > > Then in case of a DDL statement, this can potentially be unsafe to run in > parallel even with other transactional events. So for a DDL, the DDL has to > wait for all prior event groups, _and_ subsequent event groups have to wait > for the DDL. > > Slave_DDL_Events counts these occurences. > > This is what the documentation, and commit messages, should explain, I > think. > > I think the status variables describe the values for > @@default_master_connection?, this should also be explained in the > documentation. > > Why did you decide to put this information into a status variable? > Normally, > slave status is seen in SHOW SLAVE STATUS, which supports showing status > for > a particular connection without using @@default_master_connection. > > Sorry for this , I guess It was a confusion I was looking at Slave_Running this is avaliable in show status as well as show slave status. So I thought for if I want to show some information in SHOW slave status this has to be in show status. And this is wrong. Now we can see non trans events / ddl events in show slave status. Show I remove this vars from Show Status, or it is okay ? > > diff --git a/sql/log_event.h b/sql/log_event.h > > index 90900f6..579607f 100644 > > --- a/sql/log_event.h > > +++ b/sql/log_event.h > > @@ -50,6 +50,7 @@ > > #endif > > > > #include "rpl_gtid.h" > > +#include "my_atomic.h" > > Why include my_atomic.h in the header file, when you only use it in the .cc > file? > Changed. > > > + mysql_mutex_lock(&LOCK_active_mi); > > + if (master_info_index) > > + { > > + mi= master_info_index-> > > + get_master_info(&thd->variables.default_master_connection, > > + Sql_condition::WARN_LEVEL_NOTE); > > + if (mi) > > + tmp= mi->total_ddl_events; > > > + if (mi) > > + tmp= mi->total_non_trans_events; > > Better use an atomic primitive here to read the value. Taking a mutex does > not help synchronise against my_atomic_add64_explicit(). > > Changed. > > + } > > + mysql_mutex_unlock(&LOCK_active_mi); > > + if (mi) > > + *((longlong *)buff)= tmp; > > + else > > + var->type= SHOW_UNDEF; > > + > > + return 0; > > +} > > #endif /* HAVE_REPLICATION */ > > > > static int show_open_tables(THD *thd, SHOW_VAR *var, char *buff, > > > index 9365c06..a474aa5 100644 > > --- a/sql/rpl_mi.h > > +++ b/sql/rpl_mi.h > > @@ -303,6 +303,12 @@ class Master_info : public > Slave_reporting_capability > > > > /* The parallel replication mode. */ > > enum_slave_parallel_mode parallel_mode; > > + > > + /* No of DDL statements */ > > + long total_ddl_events; > > + > > + /* No of non-transactional statements*/ > > + long total_non_trans_events; > > "long" is not the appropriate type here. Certainly not since you are using > my_atomic_add64_explicit(). Use a type that is the same size on all > platforms (and why use a signed type?). > > Changed to uint64. > - Kristian. > Attached a newer version of patch , please review it. -- Regards Sachin

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[Maria-developers] CREATE SEQUENCE is coming
by Michael Widenius 18 Apr '18

18 Apr '18

Hi! For those that are trying to port applications to MariaDB from other databases or need more features than the current AUTO_INCREMENT provides, the following may be of interest: First version of sequence is pushed to bb-10.2-sequence. It should be merged to bb-10.2-compatilbity and then to 10.3 shortly (1-2 weeks). What is working for the moment: CREATE OR REPLACE [TEMPORARY] SEQUENCE [IF NOT EXISTS] name [ INCREMENT [ BY | = ] increment ] [ MINVALUE [=] minvalue | NO MINVALUE ] [ MAXVALUE [=] maxvalue | NO MAXVALUE ] [ START [ WITH | = ] start ] [ CACHE [=] cache ] [ [ NO ] CYCLE ] ENGINE=xxx COMMENT=".." SELECT NEXT VALUE FOR sequence_name; SELECT NEXTVAL(sequence_name); SELECT PREVIOUS VALUE FOR sequence_name; SELECT LASTVAL(sequence_name); SHOW CREATE SEQUENCE sequence_name; SHOW CREATE TABLE sequence_name; CREATE TABLE sequence-structure ... SEQUENCE=1 ALTER TABLE sequence RENAME TO sequence2; RENAME TABLE sequence RENAME TO sequence2; DROP [TEMPORARY] SEQUENCE sequence_name [IF EXISTS] See https://jira.mariadb.org/browse/MDEV-10139 for progress. See commit messages in bb-10.2-sequence for what is still to be done. Some documentation can be found at: https://mariadb.com/kb/en/mariadb/create-sequence/ This will be improved as the work progress. One of the goals with the SEQUENCE implementation is that all old tools, like mysqldump, should work unchanged, while still keeping normal usage of sequence standard compatibly. The make this possible, the sequence is currently implemented as a table with a few exclusive properties. The main disadvantage of having sequence as a table is that it uses the same name space as tables. In other words, you can't have a table and a sequence of the same name. The benefit is that sequences shows up in 'show tables', one can create a sequence also with 'create table' and drop it with 'drop table'. One can select from it as from any other table. This ensures that all old tools that works with tables should work with sequences. The special properties for sequence tables are: - A sequence table has always one row. - When one creates a sequence, either with CREATE TABLE or CREATE SEQUENCE, one row will be inserted. - Normal table options works for CREATE SEQUENCE. One can use ENGINE=xxx, COMMENT=xxx etc. - If one tries to insert into a sequence table, the single row will be updated. This allows mysqldump to work but also gives the additional benefit that one can change all properties of a sequence with a single insert. New applications can of course also use ALTER SEQUENCE. - Updates to the sequence table will change the single row. - Doing a select on the sequence shows the current state of the sequence, except the values that are reserved in the cache. The column 'next_value' shows the next value not reserved by the cache. - Truncate on a sequence table will give an error. - Alter table and rename works on sequences. - If one creates a sequence with INCREMENT 0, then the sequence will use auto_increment_increment and auto_increment_offset for the sequence, just like AUTO_INCREMENT. This allows sequences to work reliable in a master-master environment and with Galera. Internally sequence tables are created as a normal table without rollback (InnoDB, Aria and MySAM supports this) with is wrapped by a sequence engine. This allowed me to create sequences with almost no performance impact for normal tables. (The cost is one 'if' per insert if binary log is enabled). MariaDB 10.3 will support both the ANSI SQL and Oracle syntax for creating and accessing sequences. As ANSI SQL doesn't have an easy access to the last generated value, 103 also supports 'PREVIOUS VALUE FOR sequence_name', like IBM DB2, and LASTVAL(sequence_name) as PostgreSQL. I want to thank Jianwe Zhao from Aliyun for his work on SEQUENCE in AliSQL which gave me ideas and inspiration for this work. I also want to thank Marko Mäkelä for his help in the InnoDB part of the code. There is still a lot of work to fix edge cases, but in the current implementation most major things seams to work... Comments, suggestions or questions? Regards, Monty

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[Maria-developers] Please review MDEV-11292 Item_func_sp::fix_length_and_dec() does not set collation derivation properly
by Alexander Barkov 20 Nov '17

20 Nov '17

Hello Alexey, Please review a patch for MDEV-11292 (for 10.3). Thanks.

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[Maria-developers] RFC: new replication feature "per-engine mysql.gtid_slave pos"
by Kristian Nielsen 11 Jul '17

11 Jul '17

I plan to implement MDEV-12179, per-engine mysql.gtid_slave_pos. Here is a description of the high-level design, as a request for comments and/or suggestion for changes. The purpose of this is to fix a serious performance issue in replication when multiple storage engines are used. Every replicated transaction updates the replication GTID position in table mysql.gtid_slave_pos. There is a large overhead if that table is using another storage engine than the rest of the transaction, as then a cross-engine XA transaction needs to be done. But if more than one storage engine is used on a server, some replicated transactions will necessarily end up being cross-engine. This problem becomes more interesting to fix with the new interest in MyRocks. Though it already exists also for eg. people using MyISAM or TokuDB simultaneously with InnoDB, for example. The basic idea is to create multiple copies of the table, eg. mysql.gtid_slave_pos_innodb and mysql.gtid_slave_pos_myrocks. This way, an InnoDB transaction can update the InnoDB version of the table, and similar for other engines. To enable the feature, the DBA would create extra copies of the table for the engines she wants: CREATE TABLE mysql.gtid_slave_pos_myrocks LIKE mysql.gtid_slave_pos; ALTER TABLE mysql.gtid_slave_pos_myrocks ENGINE=myrocks; The server will look for all tables called mysql.gtid_slave_pos* at startup, as well as on each START SLAVE. This method makes migration from earlier versions simple. MariaDB already has the ability to work with multiple redundant rows in the mysql.gtid_slave_pos table. The column "sub_id" provides a version to identify the most recent entry. So the server just needs to read multiple tables (if present), and pick the newest version amongst all rows. Thus, the new feature is compatible with older versions without any schema changes. I think it is better than automatically creating copies of the table for all engines; it is often the case that an engine (eg. TokuDB) is available in the server binary, but the user does not want any tables created in that engine. This means that no speedup is obtained if the user does not create additional mysql.gtid_slave_pos* tables. (However, things should still work fine, thanks to XA synchronising cross-engine transactions). - Kristian.

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[Maria-developers] MDEV-10306 Wrong results with combination of CONCAT, SUBSTR and CONVERT in subquery
by Alexander Barkov 16 Jun '17

16 Jun '17

Hello Sergei, Please review a fix for MDEV-10306. Thanks!

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[Maria-developers] MDEV-10142 - bb-10.2-compatibility / MDEV-10574
by jerome brauge 28 Apr '17

28 Apr '17

Hello Alexander, Sometime ago, when I ask you about plan for MDEV-10574, you replied : >The current plan is to do these transformations: > >1. Transform Insert >- insert values ("") -> insert values (null) > >2. Transform Select > >- where v=x => (v <> "" and V=X) >- where v is null => (v="" or v is null) > >We didn't plan to change functions yet. Thanks for bringing this up. >We'll discuss this. I've done some tests just by changing : - insert an Item_null instead of an Item_string when $1.length==0 in rule text_literal of sql_yacc_ora.yy - return null instead of an empty string in Item_str_func::make_empty_result My first tests seem promising. Of course this solution does not allow to "see" the records created with empty strings as null values. I don't see the importance of being able to do this in a transparent way. We can explicitly select these row by adding rtrim on these columns. If you are interesting, I can begin to write a test to evaluate the coverage of this solution. Best regard. Jérôme.

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[Maria-developers] Item_func_group_concat::fix_fields - indentation and check positioning?
by Daniel Black 18 Apr '17

18 Apr '17

I came across the following gcc warning (6.3.1) sql/item_sum.cc: In member function ‘virtual bool Item_func_group_concat::fix_fields(THD*, Item**)’: sql/item_sum.cc:3478:5: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation] if ((!args[i]->fixed && ^~ sql/item_sum.cc:3482:7: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘if’ with_subselect|= args[i]->with_subselect; ^~~~~~~~~~~~~~ The with_subselect line was added in 950abd526 In context it is: Item_func_group_concat::fix_fields(THD *thd, Item **ref) { ... for (i=0 ; i < arg_count ; i++) { if ((!args[i]->fixed && args[i]->fix_fields(thd, args + i)) || args[i]->check_cols(1)) return TRUE; with_subselect|= args[i]->with_subselect; } While removing the indent would fix the warning, I'd like someone to check this line should be after the IF statement rather than before.

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Re: [Maria-developers] b4a223e3381: MDEV-10355 Weird error message upon CREATE TABLE with DEFAULT
by Sergei Golubchik 07 Apr '17

07 Apr '17

Hi, Jacob! On Mar 28, jacob.mathew(a)mariadb.com wrote: > revision-id: b4a223e338152c8764c980aeae59fb927eea1b0b (mariadb-10.2.4-98-gb4a223e3381) > parent(s): 3f7455c03008b2428fa9b364b1add4c36834ff71 > author: Jacob Mathew > committer: Jacob Mathew > timestamp: 2017-03-28 17:41:56 -0700 > message: > > MDEV-10355 Weird error message upon CREATE TABLE with DEFAULT > > Fixed handling of default values with cached temporal functions so that the > CREATE TABLE statement now succeeds. > Added clearing of cached function values to trigger function reevaluation > when updating default values and when updating virtual column values. > Fixed the error message. > Added quoting of date/time values in cases when this was omitted. > Added a test case. > Updated test result files that include date/time values that were > previously unquoted. > > diff --git a/mysql-test/r/func_default_between_temporal.result b/mysql-test/r/func_default_between_temporal.result > new file mode 100644 > index 00000000000..db9656f4d37 > --- /dev/null > +++ b/mysql-test/r/func_default_between_temporal.result > @@ -0,0 +1,15 @@ > +CREATE OR REPLACE TABLE t1 ( col INT DEFAULT ( 1 LIKE ( NOW() BETWEEN '2000-01-01' AND '2012-12-12' ) ) ); > +SHOW CREATE TABLE t1; > +Table Create Table > +t1 CREATE TABLE `t1` ( > + `col` int(11) DEFAULT (1 like (current_timestamp() between '2000-01-01 00:00:00' and '2012-12-12 00:00:00')) > +) ENGINE=MyISAM DEFAULT CHARSET=latin1 > +SET timestamp = UNIX_TIMESTAMP( '2004-04-04' ); > +INSERT INTO t1 VALUES( DEFAULT ); > +SET timestamp = DEFAULT; better use another constant here, don't rely on the current timestamp being between 2000 and 2012. I know, sounds crazy. But debian's reproducible builds (*) do everything with the system time seriously off. (*) https://wiki.debian.org/ReproducibleBuilds > +INSERT INTO t1 VALUES( DEFAULT ); > +SELECT * FROM t1; > +col > +1 > +0 > +DROP TABLE t1; > diff --git a/mysql-test/t/func_default_between_temporal.test b/mysql-test/t/func_default_between_temporal.test please, rename the test somehow or put it into default.test. "func_default" means it's about a DEFAULT() function, but your test is not. > new file mode 100644 > index 00000000000..6cbd5a342c6 > --- /dev/null > +++ b/mysql-test/t/func_default_between_temporal.test > @@ -0,0 +1,11 @@ Start the test with a header, like # # MDEV-10355 Weird error message upon CREATE TABLE with DEFAULT # > +CREATE OR REPLACE TABLE t1 ( col INT DEFAULT ( 1 LIKE ( NOW() BETWEEN '2000-01-01' AND '2012-12-12' ) ) ); > +SHOW CREATE TABLE t1; > + > +SET timestamp = UNIX_TIMESTAMP( '2004-04-04' ); > +INSERT INTO t1 VALUES( DEFAULT ); > +SET timestamp = DEFAULT; > +INSERT INTO t1 VALUES( DEFAULT ); > + > +SELECT * FROM t1; > + > +DROP TABLE t1; > diff --git a/sql/item.cc b/sql/item.cc > index c34d27fa63b..ee3e43b60ad 100644 > --- a/sql/item.cc > +++ b/sql/item.cc > @@ -616,8 +616,9 @@ void Item::print_value(String *str) > str->append("NULL"); > else > { > - switch (result_type()) { > + switch (cmp_type()) { > case STRING_RESULT: > + case TIME_RESULT: okay, that fixes quoting. good. > append_unescaped(str, ptr->ptr(), ptr->length()); > break; > case DECIMAL_RESULT: > @@ -9433,17 +9433,26 @@ void Item_cache::store(Item *item) > > void Item_cache::print(String *str, enum_query_type query_type) > { > - if (value_cached) > + if ( example && ( example->type() == FUNC_ITEM ) && // There is a cached function item > + ( query_type & QT_ITEM_IDENT_SKIP_TABLE_NAMES ) ) // Caller is show-create-table 1. better test for QT_ITEM_CACHE_WRAPPER_SKIP_DETAILS 2. Why the test for FUNC_ITEM? I don't see any logical reason why skipping of "<cache>" should only apply to functions. and please watch the spacing around parentheses, try to use the same coding style as the rest of the code > { > - print_value(str); > - return; > + // Instead of "cache" or the cached value, print the function name > + example->print( str, query_type ); > } > - str->append(STRING_WITH_LEN("<cache>(")); > - if (example) > - example->print(str, query_type); > else > - Item::print(str, query_type); > - str->append(')'); > + { > + if (value_cached) Indentation. please, try to use the same coding style as the rest of the code > + { > + print_value(str); > + return; > + } It's not very logical that the value is not printed if one doesn't want "<cache>". I think this method could be like this: ================================== void Item_cache::print(String *str, enum_query_type query_type) { if (value_cached && !(query_type & QT_NO_DATA_EXPANSION)) { print_value(str); return; } if (!(query_type & QT_ITEM_CACHE_WRAPPER_SKIP_DETAILS)) str->append(STRING_WITH_LEN("<cache>(")); if (example) example->print(str, query_type); else Item::print(str, query_type); if (!(query_type & QT_ITEM_CACHE_WRAPPER_SKIP_DETAILS)) str->append(')'); } ================================== That is, print the value unless QT_NO_DATA_EXPANSION is specified. Print "<cache>" unless QT_ITEM_CACHE_WRAPPER_SKIP_DETAILS is specified. And Virtual_column_info::print() should also specify QT_NO_DATA_EXPANSION. > + str->append(STRING_WITH_LEN("<cache>(")); > + if (example) > + example->print(str, query_type); > + else > + Item::print(str, query_type); > + str->append(')'); > + } > } > > /** > diff --git a/sql/item.h b/sql/item.h > index 67640ce5f4d..222f8580cb4 100644 > --- a/sql/item.h > +++ b/sql/item.h > @@ -1653,6 +1653,7 @@ class Item: public Value_source, > { > return mark_unsupported_function(full_name(), arg, VCOL_IMPOSSIBLE); > } > + virtual bool clear_cached_function_value(void *arg) { return 0; } > virtual bool check_field_expression_processor(void *arg) { return 0; } > virtual bool check_func_default_processor(void *arg) { return 0; } > /* > @@ -5450,8 +5451,21 @@ class Item_cache: public Item_basic_constant, > } > bool check_vcol_func_processor(void *arg) > { > + if ( example ) > + { > + return example->check_vcol_func_processor( arg ); whitespace around parentheses and indentation > + } > return mark_unsupported_function("cache", arg, VCOL_IMPOSSIBLE); > } > + bool clear_cached_function_value( void *arg ) > + { > + if ( example && example->type() == Item::FUNC_ITEM ) > + { > + // Clear the cached function value to trigger reevaluation > + clear(); > + } > + return false; > + } Why did you need a dedicated clear_cached_function_value() processor? There's Item::cleanup() that should be called from fix_session_vcol_expr(). Oh, okay, I see two issues here. First, item->cleanup() does not recurse into function arguments. That's my bug, I should've used something like - vcol->expr->cleanup(); + vcol->expr->walk(&Item::cleanup_excluding_fields_processor, 0, 0); It has to be fixed, it's a genuine bug. A test case could be create table t1 (n varchar(100), cu varchar(100) default current_user(), uc varchar(100) default concat(current_user())); create definer=foo@localhost view v1 as select * from t1; insert v1 (n) values ('v1'); select * from t1; This is a slightly modified test from default_session.test file. Second, it's incorrect for Item_cache to use simply example->check_vcol_func_processor(arg); because caching requires re-fixing, even if the underlying example item doesn't. So, this should be something like bool check_vcol_func_processor(void *arg) { if ( example ) { Item::vcol_func_processor_result *res= (Item::vcol_func_processor_result*)arg; example->check_vcol_func_processor(arg); if (res->errors & VCOL_NOT_STRICTLY_DETERMINISTIC) res->errors|= VCOL_SESSION_FUNC; return false; } return mark_unsupported_function("cache", arg, VCOL_IMPOSSIBLE); } this sets VCOL_SESSION_FUNC flag, which will require item to be re-fixed for every statement. But doesn't set it for true constants. With these two fixes Item_cache::cleanup() { clear(); } should works just fine. > /** > Check if saved item has a non-NULL value. > Will cache value of saved item if not already done. > diff --git a/sql/table.cc b/sql/table.cc > index 3a08d1e49ea..9ae035e41aa 100644 > --- a/sql/table.cc > +++ b/sql/table.cc > @@ -2802,9 +2802,9 @@ static bool fix_and_check_vcol_expr(THD *thd, TABLE *table, > > int error= func_expr->walk(&Item::check_vcol_func_processor, 0, &res); > if (error || (res.errors & VCOL_IMPOSSIBLE)) > - { // this can only happen if the frm was corrupted > + { this comment is still true, don't delete it. and there's no need to pass the type inside anymore. > my_error(ER_VIRTUAL_COLUMN_FUNCTION_IS_NOT_ALLOWED, MYF(0), res.name, > - "???", "?????"); > + vcol_type_name((enum_vcol_info_type) vcol_type), vcol->name.str); > DBUG_RETURN(1); > } > vcol->flags= res.errors; > @@ -7374,6 +7374,10 @@ int TABLE::update_virtual_fields(handler *h, enum_vcol_update_mode update_mode) > > if (update) > { > + // Clear any cached function values in the virtual field expression > + // to trigger their reevaluation > + vcol_info->expr->walk( &Item::clear_cached_function_value, 0, 0 ); // Always returns 0 There's no need to do that for every update_virtual_fields(), that is, no need to do it for every row, only needs to be done once per statement. And fix_session_vcol_expr() will do it for you if you implement Item_cache::cleanup() and set VCOL_SESSION_FUNC and fix fix_session_vcol_expr() to cleanup recursively. > + > int field_error __attribute__((unused)) = 0; > /* Compute the actual value of the virtual fields */ > if (vcol_info->expr->save_in_field(vf, 0)) Regards, Sergei Chief Architect MariaDB and security(a)mariadb.org

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[Maria-developers] mariadb-connector-c on mingw-w64 with pthreads
by Jeroen Ooms 06 Apr '17

06 Apr '17

For the language bindings for the R programming language (RMySQL) I am building mariadb-connector-c-2.3.2 on Windows using the mingw-w64 compiler. Our mingw-w64 compilers have been configured with pthreads support (same as msys2): - i686-493-posix-dwarf-rt_v3-s for win32 - x86_64-493-posix-seh-rt_v3-s for win64 Building libmariadbclient succeeds, however when I try to link the static library into the application I get these errors: C:/Rtools/mingw_64/lib/gcc/x86_64-w64-mingw32/lib/libpthread.a(libwinpthread_la-cond.o):cond.c:(.text+0x300): multiple definition of `pthread_cond_init' libmariadbclient.a(my_pthread.c.obj):my_pthread.c:(.text+0x0): first defined here Same error for 'pthread_cond_destroy', 'pthread_cond_wait', and 'pthread_cond_timedwait'. From the source code of my_pthread.c it seems that mariadb-connector-c is indeed redefining these functions on _WIN32. I guess this assumes MSVC which does not have native pthreads? Some questions: 1. What would be the correct way to configure/build mariadb-connector-c on mingw-w64 with native pthread support? 2. Is there a cmake option to disable threading alltogether? Thank you

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