1berry/MariaDB-server
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

MDEV-36486 Optimizer hints are resolved against the INSERT part of INSERT..SELECT

Browse Source 
When processing queries like
  INSERT INTO t1 (..) SELECT .. FROM t1, t2 ...,

there is a single query block (i.e., a single SELECT_LEX) for both INSERT and
SELECT parts. During hints resolution, when hints are attached to particular
TABLE_LIST's, the search is performed by table name across the whole
query block.
So, if a table mentioned in an optimizer hint is present in the INSERT part,
the hint is attached to the that table. This is obviously wrong as
optimizer hints are supposed to only affect the SELECT part of
an INSERT..SELECT clause.

This commit disables possible attaching hints to tables in the INSERT part
and fixes some other bugs related to INSERT..SELECT statements processing
This commit is contained in:
Oleg Smirnov 2025-04-08 16:59:28 +07:00
parent b89a1e7f35
commit fa929a2be6
12 changed files with 150 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

55
mysql-test/main/opt_hints.result
View File

@ -1379,6 +1379,61 @@ SELECT
Warnings:
Warning 1064 Optimizer hint syntax error near '? bad syntax */ 1' at line 2
DROP TABLE t1;
# MDEV-36486 Optimizer hints are resolved against the INSERT part of INSERT..SELECT
CREATE TABLE t1 (a INT, KEY(a));
INSERT INTO t1 VALUES (1),(2),(3);
CREATE TABLE t2 (a INT, KEY(a));
INSERT INTO t2 VALUES (1),(2),(3);
# See that the range optimization is employed when there are no hints:
EXPLAIN EXTENDED
INSERT INTO t1 (a) SELECT a FROM t1 WHERE a>1 AND a<=3;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 range a a 5 NULL 2 100.00 Using where; Using index; Using temporary
Warnings:
Note 1003 insert into `test`.`t1`(a) select sql_buffer_result `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` > 1 and `test`.`t1`.`a` <= 3
# No range optimization any more:
EXPLAIN EXTENDED
INSERT INTO t1 (a) SELECT /*+ no_range_optimization (t1 a)*/ a FROM t1 WHERE a>1 AND a<=3;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 index a a 5 NULL 3 100.00 Using where; Using index; Using temporary
Warnings:
Note 1003 insert into `test`.`t1`(a) select /*+ NO_RANGE_OPTIMIZATION(`t1`@`select#2` `a`) */ sql_buffer_result `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` > 1 and `test`.`t1`.`a` <= 3
# Alternatively, a hint may be placed next to INSERT keyword:
EXPLAIN EXTENDED
INSERT /*+ no_range_optimization (t1)*/ INTO t1 (a) SELECT a FROM t1 WHERE a>1 AND a<=3;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 index a a 5 NULL 3 100.00 Using where; Using index; Using temporary
Warnings:
Note 1003 insert into `test`.`t1`(a) select /*+ NO_RANGE_OPTIMIZATION(`t1`@`select#1`) */ sql_buffer_result `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` > 1 and `test`.`t1`.`a` <= 3
# But if hints are present at both INSERT and SELECT parts,
# those at the INSERT part are ignored:
EXPLAIN EXTENDED
INSERT /*+ no_range_optimization (t1)*/ INTO t1 (a) SELECT /*+ mrr(t1)*/ a
FROM t1 WHERE a>1 AND a<=3;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 range a a 5 NULL 2 100.00 Using where; Using index; Using temporary
Warnings:
Note 1003 insert into `test`.`t1`(a) select /*+ MRR(`t1`@`select#2`) */ sql_buffer_result `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` > 1 and `test`.`t1`.`a` <= 3
# Table `t2` cannot be resolved since it is not present in the SELECT part
# (a warning expected):
EXPLAIN EXTENDED
INSERT INTO t2 (a) SELECT /*+ no_range_optimization (t2)*/ a FROM t1 WHERE a>1 AND a<=3;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 range a a 5 NULL 2 100.00 Using where; Using index
Warnings:
Warning 4212 Unresolved table name `t2`@`select#2` for NO_RANGE_OPTIMIZATION hint
Note 1003 insert into `test`.`t2`(a) select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` > 1 and `test`.`t1`.`a` <= 3
# Alternative placement of the hint:
EXPLAIN EXTENDED
INSERT /*+ no_range_optimization (t2 ix1)*/ INTO t2 (a) SELECT a FROM t1 WHERE a>1 AND a<=3;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 range a a 5 NULL 2 100.00 Using where; Using index
Warnings:
Warning 4213 Unresolved index name `t2`@`select#1` `ix1` for NO_RANGE_OPTIMIZATION hint
Note 1003 insert into `test`.`t2`(a) select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` > 1 and `test`.`t1`.`a` <= 3
DROP TABLE t1, t2;
set optimizer_switch = DEFAULT;
set join_cache_level = DEFAULT;
#

40
mysql-test/main/opt_hints.test
View File

@ -704,6 +704,46 @@ SELECT
/*+ ? bad syntax */ 1;
DROP TABLE t1;
--echo
--echo # MDEV-36486 Optimizer hints are resolved against the INSERT part of INSERT..SELECT
--echo
CREATE TABLE t1 (a INT, KEY(a));
INSERT INTO t1 VALUES (1),(2),(3);
CREATE TABLE t2 (a INT, KEY(a));
INSERT INTO t2 VALUES (1),(2),(3);
--echo # See that the range optimization is employed when there are no hints:
EXPLAIN EXTENDED
INSERT INTO t1 (a) SELECT a FROM t1 WHERE a>1 AND a<=3;
--echo # No range optimization any more:
EXPLAIN EXTENDED
INSERT INTO t1 (a) SELECT /*+ no_range_optimization (t1 a)*/ a FROM t1 WHERE a>1 AND a<=3;
--echo # Alternatively, a hint may be placed next to INSERT keyword:
EXPLAIN EXTENDED
INSERT /*+ no_range_optimization (t1)*/ INTO t1 (a) SELECT a FROM t1 WHERE a>1 AND a<=3;
--echo # But if hints are present at both INSERT and SELECT parts,
--echo # those at the INSERT part are ignored:
EXPLAIN EXTENDED
INSERT /*+ no_range_optimization (t1)*/ INTO t1 (a) SELECT /*+ mrr(t1)*/ a
FROM t1 WHERE a>1 AND a<=3;
--echo # Table `t2` cannot be resolved since it is not present in the SELECT part
--echo # (a warning expected):
EXPLAIN EXTENDED
INSERT INTO t2 (a) SELECT /*+ no_range_optimization (t2)*/ a FROM t1 WHERE a>1 AND a<=3;
--echo # Alternative placement of the hint:
EXPLAIN EXTENDED
INSERT /*+ no_range_optimization (t2 ix1)*/ INTO t2 (a) SELECT a FROM t1 WHERE a>1 AND a<=3;
DROP TABLE t1, t2;
set optimizer_switch = DEFAULT;
set join_cache_level = DEFAULT;

2
sql/opt_hints_parser.cc
View File

@ -475,7 +475,7 @@ bool Parser::Index_level_hint::resolve(Parse_context *pc) const
if (!idx)
{
idx= new (pc->thd->mem_root)
Opt_hints_key(index_name_sys, tab, pc->thd->mem_root);
Opt_hints_key(index_name_sys, tab, pc->thd->mem_root);
tab->register_child(idx);
}

46
sql/sql_base.cc
View File

@ -8229,7 +8229,6 @@ void make_leaves_list(THD *thd, List<TABLE_LIST> &list, TABLE_LIST *tables,
refresh It is only refresh for subquery
select_insert It is SELECT ... INSERT command
full_table_list a parameter to pass to the make_leaves_list function
resolve_opt_hints Whether optimizer hints must be resolved here
NOTE
Check also that the 'used keys' and 'ignored keys' exists and set up the
@ -8249,7 +8248,7 @@ void make_leaves_list(THD *thd, List<TABLE_LIST> &list, TABLE_LIST *tables,
bool setup_tables(THD *thd, Name_resolution_context *context,
List<TABLE_LIST> *from_clause, TABLE_LIST *tables,
List<TABLE_LIST> &leaves, bool select_insert,
bool full_table_list, bool resolve_opt_hints)
bool full_table_list)
{
uint tablenr= 0;
List_iterator<TABLE_LIST> ti(leaves);
@ -8285,18 +8284,23 @@ bool setup_tables(THD *thd, Name_resolution_context *context,
leaves.push_back(table_list, thd->mem_root);
}
bool is_insert_tables_num_set= false;
/*
This variable is only used for INSERT..SELECT's:
true: processing the INSERT part of an INSERT..SELECT
false: processing the SELECT part of it
*/
bool is_insert_part= true;
while ((table_list= ti++))
{
TABLE *table= table_list->table;
if (table && !table->pos_in_table_list)
table->pos_in_table_list= table_list;
if (select_insert && !is_insert_tables_num_set &&
if (select_insert && is_insert_part &&
table_list->top_table() == first_select_table)
{
/* new counting for SELECT of INSERT ... SELECT command */
thd->lex->first_select_lex()->insert_tables= tablenr;
is_insert_tables_num_set= true;
is_insert_part= false;
tablenr= 0;
}
if(table_list->jtbm_subselect)
@ -8321,15 +8325,22 @@ bool setup_tables(THD *thd, Name_resolution_context *context,
DBUG_RETURN(1);
}
if (qb_hints && // QB hints initialized
!table_list->opt_hints_table) // Table hints are not adjusted yet
/*
Conditions to meet for optimizer hints resolution:
(1) QB hints initialized
(2) Table hints are not adjusted yet
(3) Table is not in the INSERT part of INSERT..SELECT
*/
if (qb_hints && // (1)
!table_list->opt_hints_table && // (2)
!(select_insert && is_insert_part)) // (3)
{
table_list->opt_hints_table=
qb_hints->fix_hints_for_table(table_list->table,
table_list->alias);
}
}
if (select_insert && !is_insert_tables_num_set)
if (select_insert && is_insert_part)
{
/*
This happens for statements like `INSERT INTO t1 SELECT 1`,
@ -8396,19 +8407,6 @@ bool setup_tables(THD *thd, Name_resolution_context *context,
if (setup_natural_join_row_types(thd, from_clause, context))
DBUG_RETURN(1);
if (resolve_opt_hints)
{
if (thd->lex->opt_hints_global && select_lex->select_number == 1)
{
thd->lex->opt_hints_global->fix_hint(thd);
/*
There's no need to call opt_hints_global->check_unresolved(),
this is done for each query block individually
*/
}
if (qb_hints)
qb_hints->check_unfixed(thd);
}
DBUG_RETURN(0);
}
@ -8428,7 +8426,6 @@ bool setup_tables(THD *thd, Name_resolution_context *context,
select_insert It is SELECT ... INSERT command
want_access what access is needed
full_table_list a parameter to pass to the make_leaves_list function
resolve_opt_hints Whether optimizer hints must be resolved here
NOTE
a wrapper for check_tables that will also check the resulting
@ -8445,13 +8442,12 @@ bool setup_tables_and_check_access(THD *thd, Name_resolution_context *context,
bool select_insert,
privilege_t want_access_first,
privilege_t want_access,
bool full_table_list,
bool resolve_opt_hints)
bool full_table_list)
{
DBUG_ENTER("setup_tables_and_check_access");
if (setup_tables(thd, context, from_clause, tables,
leaves, select_insert, full_table_list, resolve_opt_hints))
leaves, select_insert, full_table_list))
DBUG_RETURN(TRUE);
List_iterator<TABLE_LIST> ti(leaves);

5
sql/sql_base.h
View File

@ -228,7 +228,7 @@ Item ** find_item_in_list(Item *item, List<Item> &items, uint *counter,
bool setup_tables(THD *thd, Name_resolution_context *context,
List<TABLE_LIST> *from_clause, TABLE_LIST *tables,
List<TABLE_LIST> &leaves, bool select_insert,
bool full_table_list, bool resolve_opt_hints);
bool full_table_list);
bool setup_tables_and_check_access(THD *thd,
Name_resolution_context *context,
List<TABLE_LIST> *from_clause,
@ -237,8 +237,7 @@ bool setup_tables_and_check_access(THD *thd,
bool select_insert,
privilege_t want_access_first,
privilege_t want_access,
bool full_table_list,
bool resolve_opt_hints);
bool full_table_list);
bool wait_while_table_is_used(THD *thd, TABLE *table,
enum ha_extra_function function);

4
sql/sql_delete.cc
View File

@ -1880,11 +1880,11 @@ bool Sql_cmd_delete::prepare_inner(THD *thd)
if (setup_tables_and_check_access(thd, &select_lex->context,
&select_lex->top_join_list,
table_list, select_lex->leaf_tables,
false, DELETE_ACL, SELECT_ACL, true, false))
false, DELETE_ACL, SELECT_ACL, true))
DBUG_RETURN(TRUE);
if (setup_tables(thd, &select_lex->context, &select_lex->top_join_list,
table_list, select_lex->leaf_tables, false, false, true))
table_list, select_lex->leaf_tables, false, false))
DBUG_RETURN(TRUE);
if (!multitable)

2
sql/sql_help.cc
View File

@ -801,7 +801,7 @@ static bool init_items_for_help_command(THD *thd,
if (setup_tables(thd, &first_select_lex->context,
&first_select_lex->top_join_list,
&tables[0], leaves, false, false, true))
&tables[0], leaves, false, false))
return true;
memcpy((char*) used_fields, (char*) init_used_fields,

2
sql/sql_insert.cc
View File

@ -1647,7 +1647,7 @@ static bool mysql_prepare_insert_check_table(THD *thd, TABLE_LIST *table_list,
table_list,
thd->lex->first_select_lex()->leaf_tables,
select_insert, INSERT_ACL, SELECT_ACL,
true, true))
true))
DBUG_RETURN(TRUE);
if (insert_into_view && !fields.elements)

12
sql/sql_lex.cc
View File

@ -11189,6 +11189,18 @@ bool LEX::parsed_insert_select(SELECT_LEX *first_select)
SELECT_LEX *blt __attribute__((unused))= pop_select();
DBUG_ASSERT(blt == &builtin_select);
push_select(first_select);
// INSERT..SELECT allows placing hints next to either INSERT or SELECT, i.e.:
// `INSERT /* hint(t1) */ INTO t2 SELECT a FROM t1` or
// `INSERT INTO t2 SELECT /* hint(t1) */ a FROM t1`
// but not at both places at the same time.
// `first_select` represents the SELECT part here while `builtin_select` -
// the INSERT part. Future processing will proceed with `first_select`,
// so transfer the hints from `builtin_select` to `first_select` in case
// they were not already set. If hints are present for both INSERT and SELECT
// parts, SELECT part hints are preserved while INSERT part hints are discarded
if (!first_select->opt_hints_qb && blt->opt_hints_qb)
first_select->opt_hints_qb= blt->opt_hints_qb;
return false;
}

2
sql/sql_load.cc
View File

@ -419,7 +419,7 @@ int mysql_load(THD *thd, const sql_exchange *ex, TABLE_LIST *table_list,
thd->lex->first_select_lex()->leaf_tables,
FALSE,
INSERT_ACL | UPDATE_ACL,
INSERT_ACL | UPDATE_ACL, false, true))
INSERT_ACL | UPDATE_ACL, false))
DBUG_RETURN(-1);
if (!table_list->table || // do not support join view
!table_list->single_table_updatable() || // and derived tables

13
sql/sql_select.cc
View File

@ -1468,9 +1468,20 @@ JOIN::prepare(TABLE_LIST *tables_init, COND *conds_init, uint og_num,
if (!(select_options & OPTION_SETUP_TABLES_DONE) &&
setup_tables_and_check_access(thd, &select_lex->context, join_list,
tables_list, select_lex->leaf_tables,
false, SELECT_ACL, SELECT_ACL, false, true))
false, SELECT_ACL, SELECT_ACL, false))
DBUG_RETURN(-1);
if (thd->lex->opt_hints_global && select_lex->select_number == 1)
{
thd->lex->opt_hints_global->fix_hint(thd);
/*
There's no need to call opt_hints_global->check_unresolved(),
this is done for each query block individually
*/
}
if (select_lex->opt_hints_qb)
select_lex->opt_hints_qb->check_unfixed(thd);
/* System Versioning: handle FOR SYSTEM_TIME clause. */
if (select_lex->vers_setup_conds(thd, tables_list) < 0)
DBUG_RETURN(-1);

4
sql/sql_update.cc
View File

@ -1672,7 +1672,7 @@ bool Multiupdate_prelocking_strategy::handle_end(THD *thd)
if (setup_tables_and_check_access(thd, &select_lex->context,
&select_lex->top_join_list, table_list, select_lex->leaf_tables,
false, UPDATE_ACL, SELECT_ACL, true, false))
false, UPDATE_ACL, SELECT_ACL, true))
DBUG_RETURN(1);
if (table_list->has_period() &&
@ -3118,7 +3118,7 @@ bool Sql_cmd_update::prepare_inner(THD *thd)
DBUG_RETURN(TRUE);
if (setup_tables(thd, &select_lex->context, &select_lex->top_join_list,
table_list, select_lex->leaf_tables, false, false, true))
table_list, select_lex->leaf_tables, false, false))
DBUG_RETURN(TRUE);
if (select_lex->vers_setup_conds(thd, table_list))