revision-id: 08cc519cd09dfdc5783a04c4eeba587c08c24ebb (mariadb-10.5.2-567-g08cc519cd09) parent(s): c071cc3455b61b8f757b13ed1e4a5aa8b43423c9 author: Sergei Petrunia committer: Sergei Petrunia timestamp: 2021-04-16 17:45:35 +0300 message: Cleanup: fake_select_lex->select_number=FAKE_SELECT_LEX_ID, not [U]INT_MAX SELECT_LEX objects that are "fake_select_lex" (i.e read UNION output) used both INT_MAX and UINT_MAX as select_number. - mysql_explain_union() assigned UINT_MAX - st_select_lex_unit::add_fake_select_lex assigned INT_MAX This didn't matter initially (before EXPLAIN FORMAT=JSON), because the code had no checks for this value. EXPLAIN FORMAT=JSON and later other features did introduce checks for select_number values. The check had to check for two constants and looked really confusing. This patch joins the two constants into one - FAKE_SELECT_LEX_ID. --- sql/my_json_writer.h | 2 +- sql/sql_explain.h | 16 ++++++++-------- sql/sql_parse.cc | 2 +- sql/sql_select.cc | 11 ++++------- sql/sql_tvc.cc | 3 +-- 5 files changed, 15 insertions(+), 19 deletions(-) diff --git a/sql/my_json_writer.h b/sql/my_json_writer.h index bc8002de529..27aec74d08d 100644 --- a/sql/my_json_writer.h +++ b/sql/my_json_writer.h @@ -491,7 +491,7 @@ class Json_writer_object : public Json_writer_struct if (my_writer) { add_member("select_id"); - if (unlikely(select_number >= INT_MAX)) + if (unlikely(select_number == FAKE_SELECT_LEX_ID)) context.add_str("fake"); else context.add_ll(static_cast<longlong>(select_number)); diff --git a/sql/sql_explain.h b/sql/sql_explain.h index 9090416847f..42590e0bea0 100644 --- a/sql/sql_explain.h +++ b/sql/sql_explain.h @@ -74,7 +74,7 @@ class Json_writer; *************************************************************************************/ -const int FAKE_SELECT_LEX_ID= (int)UINT_MAX; +const uint FAKE_SELECT_LEX_ID= UINT_MAX; class Explain_query; @@ -108,7 +108,7 @@ class Explain_node : public Sql_alloc }; virtual enum explain_node_type get_type()= 0; - virtual int get_select_id()= 0; + virtual uint get_select_id()= 0; /** expression cache statistics @@ -166,9 +166,9 @@ class Explain_basic_join : public Explain_node bool add_table(Explain_table_access *tab, Explain_query *query); - int get_select_id() { return select_id; } + uint get_select_id() { return select_id; } - int select_id; + uint select_id; int print_explain(Explain_query *query, select_result_sink *output, uint8 explain_flags, bool is_analyze); @@ -352,7 +352,7 @@ class Explain_union : public Explain_node enum explain_node_type get_type() { return EXPLAIN_UNION; } unit_common_op operation; - int get_select_id() + uint get_select_id() { DBUG_ASSERT(union_members.elements() > 0); return union_members.at(0); @@ -879,7 +879,7 @@ class Explain_update : public Explain_node {} virtual enum explain_node_type get_type() { return EXPLAIN_UPDATE; } - virtual int get_select_id() { return 1; /* always root */ } + virtual uint get_select_id() { return 1; /* always root */ } const char *select_type; @@ -959,7 +959,7 @@ class Explain_insert : public Explain_node StringBuffer<64> table_name; enum explain_node_type get_type() { return EXPLAIN_INSERT; } - int get_select_id() { return 1; /* always root */ } + uint get_select_id() { return 1; /* always root */ } int print_explain(Explain_query *query, select_result_sink *output, uint8 explain_flags, bool is_analyze); @@ -986,7 +986,7 @@ class Explain_delete: public Explain_update bool deleting_all_rows; virtual enum explain_node_type get_type() { return EXPLAIN_DELETE; } - virtual int get_select_id() { return 1; /* always root */ } + virtual uint get_select_id() { return 1; /* always root */ } virtual int print_explain(Explain_query *query, select_result_sink *output, uint8 explain_flags, bool is_analyze); diff --git a/sql/sql_parse.cc b/sql/sql_parse.cc index 3f0e71c747f..ddfc49c6d52 100644 --- a/sql/sql_parse.cc +++ b/sql/sql_parse.cc @@ -8954,7 +8954,7 @@ bool st_select_lex_unit::add_fake_select_lex(THD *thd_arg) DBUG_RETURN(1); fake_select_lex->include_standalone(this, (SELECT_LEX_NODE**)&fake_select_lex); - fake_select_lex->select_number= INT_MAX; + fake_select_lex->select_number= FAKE_SELECT_LEX_ID; fake_select_lex->parent_lex= thd_arg->lex; /* Used in init_query. */ fake_select_lex->make_empty_select(); fake_select_lex->set_linkage(GLOBAL_OPTIONS_TYPE); diff --git a/sql/sql_select.cc b/sql/sql_select.cc index dacd636985a..5f974397b10 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -1585,7 +1585,7 @@ bool JOIN::build_explain() JOIN_TAB *curr_tab= join_tab + exec_join_tab_cnt(); for (uint i= 0; i < aggr_tables; i++, curr_tab++) { - if (select_nr == INT_MAX) + if (select_nr == FAKE_SELECT_LEX_ID) { /* this is a fake_select_lex of a union */ select_nr= select_lex->master_unit()->first_select()->select_number; @@ -4208,14 +4208,12 @@ bool JOIN::save_explain_data(Explain_query *output, bool can_overwrite, If there is SELECT in this statement with the same number it must be the same SELECT */ - DBUG_ASSERT(select_lex->select_number == UINT_MAX || - select_lex->select_number == INT_MAX || !output || + DBUG_ASSERT(select_lex->select_number == FAKE_SELECT_LEX_ID || !output || !output->get_select(select_lex->select_number) || output->get_select(select_lex->select_number)->select_lex == select_lex); - if (select_lex->select_number != UINT_MAX && - select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && + if (select_lex->select_number != FAKE_SELECT_LEX_ID && have_query_plan != JOIN::QEP_NOT_PRESENT_YET && have_query_plan != JOIN::QEP_DELETED && // this happens when there was // no QEP ever, but then @@ -27780,8 +27778,7 @@ void st_select_lex::print(THD *thd, String *str, enum_query_type query_type) if ((query_type & QT_SHOW_SELECT_NUMBER) && thd->lex->all_selects_list && thd->lex->all_selects_list->link_next && - select_number != UINT_MAX && - select_number != INT_MAX) + select_number != FAKE_SELECT_LEX_ID) { str->append("/* select#"); str->append_ulonglong(select_number); diff --git a/sql/sql_tvc.cc b/sql/sql_tvc.cc index 6984fdd6bcf..576927ea086 100644 --- a/sql/sql_tvc.cc +++ b/sql/sql_tvc.cc @@ -397,8 +397,7 @@ bool table_value_constr::optimize(THD *thd) create_explain_query_if_not_exists(thd->lex, thd->mem_root); have_query_plan= QEP_AVAILABLE; - if (select_lex->select_number != UINT_MAX && - select_lex->select_number != INT_MAX /* this is not a UNION's "fake select */ && + if (select_lex->select_number != FAKE_SELECT_LEX_ID && have_query_plan != QEP_NOT_PRESENT_YET && thd->lex->explain && // for "SET" command in SPs. (!thd->lex->explain->get_select(select_lex->select_number)))