Before this fix, a IN predicate of the form: "IN (( subselect ))", with two
parenthesis, would be evaluated as a single row subselect: if the subselect
returns more that 1 row, the statement would fail.
The SQL:2003 standard defines a special exception in the specification,
and mandates that this particular form of IN predicate shall be equivalent
to "IN ( subselect )", which involves a table subquery and works with more
than 1 row.
This fix implements "IN (( subselect ))", "IN ((( subselect )))" etc
as per the SQL:2003 requirement.
All the details related to the implementation of this change have been
commented in the code, and the relevant sections of the SQL:2003 spec
are given for reference, so they are not repeated here.
Having access to the spec is a requirement to review in depth this patch.
mysql-test/r/subselect.result:
Implement IN predicate special exceptions with subselects.
mysql-test/t/subselect.test:
Implement IN predicate special exceptions with subselects.
sql/item_subselect.cc:
Implement IN predicate special exceptions with subselects.
sql/item_subselect.h:
Implement IN predicate special exceptions with subselects.
sql/sql_yacc.yy:
Implement IN predicate special exceptions with subselects, cleanup.
Before this fix, a IN predicate of the form: "IN (( subselect ))", with two
parenthesis, would be evaluated as a single row subselect: if the subselect
returns more that 1 row, the statement would fail.
The SQL:2003 standard defines a special exception in the specification,
and mandates that this particular form of IN predicate shall be equivalent
to "IN ( subselect )", which involves a table subquery and works with more
than 1 row.
This fix implements "IN (( subselect ))", "IN ((( subselect )))" etc
as per the SQL:2003 requirement.
All the details related to the implementation of this change have been
commented in the code, and the relevant sections of the SQL:2003 spec
are given for reference, so they are not repeated here.
Having access to the spec is a requirement to review in depth this patch.
The bug report has demonstrated the following two problems.
1. If an ORDER/GROUP BY list includes a constant expression being
optimized away and, at the same time, containing single-row
subselects that return more that one row, no error is reported.
Strictly speaking the standard allows to ignore error in this case.
Yet, now a corresponding fatal error is reported in this case.
2. If a query requires sorting by expressions containing single-row
subselects that, however, return more than one row, then the execution
of the query may cause a server crash.
To fix this some code has been added that blocks execution of a subselect
item in case of a fatal error in the method Item_subselect::exec.
mysql-test/r/subselect.result:
Added a test cases for bug #24653.
mysql-test/t/subselect.test:
Added a test cases for bug #24653.
sql/filesort.cc:
Fixed bug #24653.
Added a check for fatal error after reading the next row from the table
in the function find_all_keys.
sql/item.cc:
Fixed bug #24653.
Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item.h:
Fixed bug #24653.
Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item_cmpfunc.cc:
Fixed bug #24653.
Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item_cmpfunc.h:
Fixed bug #24653.
Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item_func.cc:
Fixed bug #24653.
Down-ported calculation of the attribute with_subselect of for Item objects.
sql/item_subselect.cc:
Fixed bug #24653.
Added a check for fatal error in the method Item_subselect::exec
to block evaluation of subselects in erroneous situations.
Down-ported calculation of the attribute with_subselect of for Item objects.
sql/sql_select.cc:
Fixed bug #24653.
Added a check to verify that any constant expression used
in ORDER BY and/or GROUP BY lists which is optimized away
does not contain subselects returning more than one row.
If it does a fatal error is reported.
The bug report has demonstrated the following two problems.
1. If an ORDER/GROUP BY list includes a constant expression being
optimized away and, at the same time, containing single-row
subselects that return more that one row, no error is reported.
Strictly speaking the standard allows to ignore error in this case.
Yet, now a corresponding fatal error is reported in this case.
2. If a query requires sorting by expressions containing single-row
subselects that, however, return more than one row, then the execution
of the query may cause a server crash.
To fix this some code has been added that blocks execution of a subselect
item in case of a fatal error in the method Item_subselect::exec.
into macbook.gmz:/Users/kgeorge/mysql/work/merge-5.1-opt
mysql-test/r/func_in.result:
Auto merged
mysql-test/r/range.result:
Auto merged
mysql-test/r/select.result:
Auto merged
mysql-test/r/sp-code.result:
Auto merged
mysql-test/r/trigger.result:
Auto merged
mysql-test/r/udf.result:
Auto merged
mysql-test/r/view.result:
Auto merged
mysql-test/t/func_in.test:
Auto merged
mysql-test/t/func_str.test:
Auto merged
mysql-test/t/range.test:
Auto merged
mysql-test/t/select.test:
Auto merged
mysql-test/t/trigger.test:
Auto merged
mysql-test/t/udf.test:
Auto merged
sql/item.cc:
Auto merged
sql/item.h:
Auto merged
sql/item_cmpfunc.cc:
Auto merged
sql/item_func.cc:
Auto merged
sql/item_strfunc.cc:
Auto merged
sql/mysql_priv.h:
Auto merged
sql/opt_range.h:
Auto merged
sql/sql_base.cc:
Auto merged
sql/sql_delete.cc:
Auto merged
sql/sql_insert.cc:
Auto merged
sql/sql_lex.cc:
Auto merged
sql/sql_lex.h:
Auto merged
sql/sql_prepare.cc:
Auto merged
sql/sql_select.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql/sql_union.cc:
Auto merged
sql/sql_update.cc:
Auto merged
mysql-test/r/func_str.result:
merge 5.0-opt -> 5.1-opt
mysql-test/r/group_by.result:
merge 5.0-opt -> 5.1-opt
mysql-test/r/insert.result:
merge 5.0-opt -> 5.1-opt
mysql-test/r/subselect.result:
merge 5.0-opt -> 5.1-opt
mysql-test/t/group_by.test:
merge 5.0-opt -> 5.1-opt
mysql-test/t/insert.test:
merge 5.0-opt -> 5.1-opt
mysql-test/t/subselect.test:
merge 5.0-opt -> 5.1-opt
mysql-test/t/view.test:
merge 5.0-opt -> 5.1-opt
sql/item_cmpfunc.h:
merge 5.0-opt -> 5.1-opt
sql/item_strfunc.h:
merge 5.0-opt -> 5.1-opt
UNION over correlated and uncorrelated SELECTS.
In such subqueries each uncorrelated SELECT should be considered as
uncacheable. Otherwise join_free is called for it and in many cases
it causes some problems.
mysql-test/r/subselect.result:
Added a test case for bug #25219.
mysql-test/t/subselect.test:
Added a test case for bug #25219.
sql/mysql_priv.h:
Fixed bug #25219: crash for a query that contains an EXIST subquery with
UNION over correlated and uncorrelated SELECTS.
In such subqueries each uncorrelated SELECT should be considered as
uncacheable. Otherwise join_free is called for it and in many cases
it causes some problems.
Added a new flag UNCACHEABLE_UNITED for such SELECTs.
sql/sql_lex.cc:
Fixed bug #25219: crash for a query that contains an EXIST subquery with
UNION over correlated and uncorrelated SELECTS.
In such subqueries each uncorrelated SELECT should be considered as
uncacheable. Otherwise join_free is called for it and in many cases
it causes some problems.
Added a new flag UNCACHEABLE_UNITED for such SELECTs.
UNION over correlated and uncorrelated SELECTS.
In such subqueries each uncorrelated SELECT should be considered as
uncacheable. Otherwise join_free is called for it and in many cases
it causes some problems.
into macbook.local:/Users/kgeorge/mysql/work/merge-5.1-opt
mysql-test/r/distinct.result:
Auto merged
mysql-test/r/gis-rtree.result:
Auto merged
mysql-test/r/ps.result:
Auto merged
mysql-test/r/subselect.result:
Auto merged
mysql-test/r/udf.result:
Auto merged
mysql-test/t/gis-rtree.test:
Auto merged
mysql-test/t/ps.test:
Auto merged
mysql-test/t/subselect.test:
Auto merged
mysql-test/t/udf.test:
Auto merged
sql/item_subselect.cc:
Auto merged
sql/item_subselect.h:
Auto merged
sql/sql_lex.cc:
Auto merged
sql/sql_select.cc:
Auto merged
storage/myisam/mi_check.c:
Auto merged
sql/sql_udf.cc:
SCCS merged
and no WHERE condition were applied for any subquery without tables.
mysql-test/r/subselect.result:
Added a test case for bug #24670.
mysql-test/t/subselect.test:
Added a test case for bug #24670.
sql/item_subselect.cc:
Fixed bug #24670: optimizations that are legal only for subqueries without tables
and no WHERE condition were applied for any subquery without tables.
Removed an assertion that caused an abort for subqueries without tables and no
WHERE condition.
Blocked substitution of a single-row subquery without tables for the constant
row from its select list when the subquery contained a WHERE condition.
This optimization is valid only for subquries without tables with no conditions.
Any subquery without tables with WHERE clause returns NULL if the WHERE condition
is FALSE. Erroneously it was always considered as non-nullable that could trigger
another optimization concerning IS NULL predicates which is applicable only for
non-nullable expressions and ultimately led to a wrong result returned by the outer
query.
Added a proper implementation of the virtual method may_be_null for class
subselect_single_select_engine.
sql/item_subselect.h:
Fixed bug #24670: optimizations that are legal only for subqueries without tables
and no WHERE condition were applied for any subquery without tables.
Made method may_by_null for class subselect_engine vvirtual.
We create Item_cache_* object for each operand for each left operand of
a subquery predicate. We also create Item_func_conv_charset for each string
constant that needs charset conversion. So here we have Item_cache wrapped
into Item_func_conv_charset.
When Item_func_conv_charset wraps an constant Item it gets it's value
in constructor. The problem is that Item_cache is ready to be used only
at execution time, which is too late.
The fix makes Item_cache wrapping constant to get ready at fix_fields() time.
mysql-test/r/subselect.result:
test result
mysql-test/t/subselect.test:
test case
sql/item_cmpfunc.cc:
now Item_optimizer::fix_left will store constant arguments in cache
on fix_fields() stage
We create Item_cache_* object for each operand for each left operand of
a subquery predicate. We also create Item_func_conv_charset for each string
constant that needs charset conversion. So here we have Item_cache wrapped
into Item_func_conv_charset.
When Item_func_conv_charset wraps an constant Item it gets it's value
in constructor. The problem is that Item_cache is ready to be used only
at execution time, which is too late.
The fix makes Item_cache wrapping constant to get ready at fix_fields() time.
into dl145s.mysql.com:/data0/bk/team_tree_merge/MERGE/mysql-5.1-opt
client/mysqltest.c:
Auto merged
libmysql/libmysql.c:
Auto merged
mysql-test/r/information_schema.result:
Auto merged
mysql-test/t/disabled.def:
Auto merged
mysql-test/t/information_schema.test:
Auto merged
mysql-test/t/subselect.test:
Auto merged
mysql-test/t/type_newdecimal.test:
Auto merged
sql/field.cc:
Auto merged
sql/field.h:
Auto merged
sql/filesort.cc:
Auto merged
sql/handler.cc:
Auto merged
sql/item_cmpfunc.cc:
Auto merged
sql/item_func.cc:
Auto merged
sql/item_subselect.cc:
Auto merged
sql/item_sum.cc:
Auto merged
sql/item_timefunc.cc:
Auto merged
sql/mysql_priv.h:
Auto merged
sql/opt_range.cc:
Auto merged
sql/sql_base.cc:
Auto merged
sql/sql_class.h:
Auto merged
sql/sql_lex.cc:
Auto merged
sql/sql_lex.h:
Auto merged
sql/sql_parse.cc:
Auto merged
sql/sql_select.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql/sql_yacc.yy:
Auto merged
sql-common/client.c:
Auto merged
sql-common/my_time.c:
Auto merged
sql/table.cc:
Auto merged
strings/decimal.c:
Auto merged
into dl145s.mysql.com:/data0/bk/team_tree_merge/MERGE/mysql-5.0-opt
libmysql/libmysql.c:
Auto merged
mysql-test/t/subselect.test:
Auto merged
mysql-test/t/type_newdecimal.test:
Auto merged
sql/filesort.cc:
Auto merged
sql/handler.cc:
Auto merged
sql/item_cmpfunc.cc:
Auto merged
sql/item_subselect.cc:
Auto merged
sql/item_timefunc.cc:
Auto merged
sql/sql_class.h:
Auto merged
sql/sql_parse.cc:
Auto merged
sql-common/client.c:
Auto merged
sql/sql_select.cc:
Auto merged
sql/table.cc:
Auto merged
sql-common/my_time.c:
Auto merged
strings/decimal.c:
Auto merged
(Mostly in DBUG_PRINT() and unused arguments)
Fixed bug in query cache when used with traceing (--with-debug)
Fixed memory leak in mysqldump
Removed warnings from mysqltest scripts (replaced -- with #)
into mysql.com:/home/hf/work/mysql-5.1-mrg
BitKeeper/deleted/.del-bdb-deadlock.test:
Auto merged
Makefile.am:
Auto merged
include/mysql.h:
Auto merged
libmysqld/lib_sql.cc:
Auto merged
mysql-test/include/deadlock.inc:
Auto merged
mysql-test/r/order_by.result:
Auto merged
mysql-test/r/subselect.result:
Auto merged
mysql-test/r/type_newdecimal.result:
Auto merged
mysql-test/t/disabled.def:
Auto merged
mysql-test/t/flush.test:
Auto merged
mysql-test/t/flush_block_commit.test:
Auto merged
mysql-test/t/innodb-lock.test:
Auto merged
mysql-test/t/lock_multi.test:
Auto merged
mysql-test/t/rename.test:
Auto merged
mysql-test/t/show_check.test:
Auto merged
mysql-test/t/status.test:
Auto merged
mysql-test/t/subselect.test:
Auto merged
mysql-test/t/type_newdecimal.test:
Auto merged
sql/field.cc:
Auto merged
sql/field.h:
Auto merged
sql/filesort.cc:
Auto merged
sql/handler.cc:
Auto merged
sql/item.cc:
Auto merged
sql/item.h:
Auto merged
sql/item_cmpfunc.cc:
Auto merged
sql/item_func.cc:
Auto merged
sql/item_func.h:
Auto merged
sql/item_subselect.cc:
Auto merged
sql/item_subselect.h:
Auto merged
sql/item_sum.cc:
Auto merged
sql/item_sum.h:
Auto merged
sql/item_timefunc.cc:
Auto merged
sql/item_timefunc.h:
Auto merged
sql/mysql_priv.h:
Auto merged
sql/sql_base.cc:
Auto merged
sql/sql_class.h:
Auto merged
sql/sql_lex.cc:
Auto merged
sql/sql_lex.h:
Auto merged
sql/sql_select.cc:
Auto merged
sql/sql_show.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql-common/my_time.c:
Auto merged
sql/table.cc:
Auto merged
client/mysqltest.c:
merging
include/my_time.h:
merging
libmysql/libmysql.c:
merging
mysql-test/t/order_by.test:
merging
sql/sql_yacc.yy:
merging
into mysql.com:/home/hf/work/mysql-5.0-0mrg
BitKeeper/deleted/.del-mysql_client.test:
Auto merged
include/mysql.h:
Auto merged
libmysqld/lib_sql.cc:
Auto merged
mysql-test/r/order_by.result:
Auto merged
mysql-test/r/query_cache.result:
Auto merged
mysql-test/r/subselect.result:
Auto merged
mysql-test/r/type_newdecimal.result:
Auto merged
mysql-test/t/flush.test:
Auto merged
mysql-test/t/flush_block_commit.test:
Auto merged
mysql-test/t/innodb-deadlock.test:
Auto merged
mysql-test/t/innodb-lock.test:
Auto merged
mysql-test/t/lock_multi.test:
Auto merged
mysql-test/t/mysql.test:
Auto merged
mysql-test/t/query_cache.test:
Auto merged
mysql-test/t/rename.test:
Auto merged
mysql-test/t/show_check.test:
Auto merged
mysql-test/t/status.test:
Auto merged
mysql-test/t/subselect.test:
Auto merged
mysql-test/t/type_newdecimal.test:
Auto merged
sql/field.cc:
Auto merged
sql/field.h:
Auto merged
sql/handler.cc:
Auto merged
sql/item.cc:
Auto merged
sql/item.h:
Auto merged
sql/item_func.cc:
Auto merged
sql/item_func.h:
Auto merged
sql/item_subselect.cc:
Auto merged
sql/item_subselect.h:
Auto merged
sql/item_sum.cc:
Auto merged
sql/item_sum.h:
Auto merged
sql/item_timefunc.cc:
Auto merged
sql/item_timefunc.h:
Auto merged
sql/mysql_priv.h:
Auto merged
sql/protocol.cc:
Auto merged
sql/protocol.h:
Auto merged
sql/sql_base.cc:
Auto merged
sql/sql_class.h:
Auto merged
sql/sql_lex.cc:
Auto merged
sql/sql_lex.h:
Auto merged
sql/sql_parse.cc:
Auto merged
sql/sql_select.cc:
Auto merged
sql/sql_show.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql/sql_yacc.yy:
Auto merged
sql/table.cc:
Auto merged
sql-common/client.c:
Auto merged
sql-common/my_time.c:
Auto merged
Makefile.am:
merging
client/mysqltest.c:
merging
include/my_time.h:
merging
libmysql/libmysql.c:
merging
mysql-test/t/order_by.test:
merging
into mysql.com:/home/hf/work/mysql-4.1-mrg
include/mysql.h:
Auto merged
mysql-test/r/subselect.result:
Auto merged
mysql-test/t/rename.test:
Auto merged
mysql-test/t/subselect.test:
Auto merged
sql-common/client.c:
Auto merged
sql/sql_class.h:
Auto merged
Makefile.am:
merging
client/mysqltest.c:
merging
mysql-test/t/mysql_client.test:
merging
- When returning metadata for scalar subqueries the actual type of the
column was calculated based on the value type, which limits the actual
type of a scalar subselect to the set of (currently) 3 basic types :
integer, double precision or string. This is the reason that columns
of types other then the basic ones (e.g. date/time) are reported as
being of the corresponding basic type.
Fixed by storing/returning information for the column type in addition
to the result type.
mysql-test/r/subselect.result:
Bug #11032: getObject() returns a String for a sub-query of type datetime
- test case
mysql-test/t/subselect.test:
Bug #11032: getObject() returns a String for a sub-query of type datetime
- test case
sql/item_subselect.cc:
Bug #11032: getObject() returns a String for a sub-query of type datetime
- store and return the field type as well in addition to result type for
single row subqueries
sql/item_subselect.h:
Bug #11032: getObject() returns a String for a sub-query of type datetime
- store and return the field type as well in addition to result type for
single row subqueries
- When returning metadata for scalar subqueries the actual type of the
column was calculated based on the value type, which limits the actual
type of a scalar subselect to the set of (currently) 3 basic types :
integer, double precision or string. This is the reason that columns
of types other then the basic ones (e.g. date/time) are reported as
being of the corresponding basic type.
Fixed by storing/returning information for the column type in addition
to the result type.
into rurik.mysql.com:/home/igor/dev-opt/mysql-5.0-opt-bug21727
mysql-test/r/subselect.result:
Auto merged
mysql-test/t/subselect.test:
Auto merged
sql/filesort.cc:
Auto merged
sql/item_subselect.h:
Auto merged
sql/mysql_priv.h:
Auto merged
sql/records.cc:
Auto merged
sql/sql_base.cc:
Auto merged
sql/sql_select.cc:
Auto merged
sql/sql_show.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql/table.cc:
Auto merged
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Allocation of memory for the sort buffer at each evaluation of a
subquery may take a significant amount of time if the buffer is rather big.
With the fix we allocate the buffer at the first evaluation of the
subquery and reuse it at each subsequent evaluation.
mysql-test/r/subselect.result:
Added a test case for bug #21727.
mysql-test/t/subselect.test:
Added a test case for bug #21727.
sql/item_subselect.h:
Fixed bug #21727.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Added an implementation for Item_subselect::is_uncacheable()
returning TRUE if the engine if the subselect is uncacheable.
sql/mysql_priv.h:
Fixed bug #21727.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Added a new boolean parameter to the filesort_free_buffers procedure.
If the value of this parameter is TRUE the procedure frees the sort_keys
buffpek buffers.
sql/records.cc:
Fixed bug #21727.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Added a new boolean parameter to the filesort_free_buffers procedure.
If the value of this parameter is TRUE the procedure frees the sort_keys
buffpek buffers.
sql/sql_base.cc:
Fixed bug #21727.
Made sure that st_table::pos_in_table_list would be always initialized.
sql/sql_select.cc:
Fixed bug #21727.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Added a new boolean parameter to the filesort_free_buffers procedure.
If the value of this parameter is TRUE the procedure frees the sort_keys
buffpek buffers.
sql/sql_show.cc:
Fixed bug #21727.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Added a new boolean parameter to the filesort_free_buffers procedure.
If the value of this parameter is TRUE the procedure frees the sort_keys
buffpek buffers.
sql/sql_table.cc:
Fixed bug #21727.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Cleanup.
sql/table.cc:
Fixed bug #21727.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Added st_table_list::in_subselect() returning for a table the subselect that
contains the FROM list this table is taken from (if there is any).
sql/table.h:
Fixed bug #21727.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Added fields for sort_keys and buffpek buffers to the FILESORT_INFO structure.
This is a performance issue for queries with subqueries evaluation
of which requires filesort.
Allocation of memory for the sort buffer at each evaluation of a
subquery may take a significant amount of time if the buffer is rather big.
With the fix we allocate the buffer at the first evaluation of the
subquery and reuse it at each subsequent evaluation.
into siva.hindu.god:/usr/home/tim/m/bk/50
configure.in:
Auto merged
mysql-test/r/rename.result:
Auto merged
mysql-test/r/subselect.result:
Auto merged
mysql-test/r/view.result:
Auto merged
mysql-test/t/subselect.test:
Auto merged
mysql-test/t/view.test:
Auto merged
mysys/mf_iocache.c:
Auto merged
sql/item_func.cc:
Auto merged
sql/opt_range.cc:
Auto merged
sql/opt_range.h:
Auto merged
sql/sql_lex.cc:
Auto merged
sql/sql_lex.h:
Auto merged
sql/sql_select.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql/table.cc:
Auto merged
myisam/sort.c:
Manual merge
mysql-test/r/innodb_mysql.result:
Manual merge
mysql-test/t/innodb_mysql.test:
Manual merge
If elements a not top-level IN subquery were accessed by an index and
the subquery result set included a NULL value then the quantified
predicate that contained the subquery was evaluated to NULL when
it should return a non-null value.
mysql-test/r/subselect.result:
Added a test case for bug #23478.
mysql-test/t/subselect.test:
Added a test case for bug #23478.
If elements a not top-level IN subquery were accessed by an index and
the subquery result set included a NULL value then the quantified
predicate that contained the subquery was evaluated to NULL when
it should return a non-null value.
into macbook.gmz:/Users/kgeorge/mysql/work/B21798-5.0-opt-merge
sql/mysql_priv.h:
Auto merged
sql/sql_delete.cc:
Auto merged
sql/sql_select.cc:
Auto merged
sql/sql_table.cc:
Auto merged
sql/sql_update.cc:
Auto merged
mysql-test/r/subselect.result:
merge fixes for bug 21798
mysql-test/t/subselect.test:
merge fixes for bug 21798
