Added test cases for bug #7351.
item_cmpfunc.cc:
Fixed bug #7351: incorrect result for a query with a
subquery returning empty set.
If in the predicate v IN (SELECT a FROM t WHERE cond)
v is null, then the result of the predicate is either
INKNOWN or FALSE. It is FALSE if the subquery returns
an empty set.
item_subselect.cc:
Fixed bug #7351: incorrect result for a query with a
subquery returning empty set.
The problem was due to not a quite legal transformation
for 'IN' subqueries. A subquery containing a predicate
of the form
v IN (SELECT a FROM t WHERE cond)
was transformed into
EXISTS(SELECT a FROM t WHERE cond AND (a=v OR a IS NULL)).
Yet, this transformation is valid only if v is not null.
If v is null, then, in the case when
(SELECT a FROM t WHERE cond) returns an empty set the value
of the predicate is FALSE, otherwise the result of the
predicate is INKNOWN.
The fix resolves this problem by changing the result
of the transformation to
EXISTS(SELECT a FROM t WHERE cond AND (v IS NULL OR (a=v OR a IS NULL)))
in the case when v is nullable.
The new transformation prevents applying the lookup
optimization for IN subqueries. To make it still
applicable we have to introduce guarded access methods.
Logging to logging@openlogging.org accepted
sql_yacc.yy, sql_parse.cc, sql_lex.h, lex.h:
Implements the SHOW MUTEX STATUS command
set_var.cc, mysqld.cc, mysql_priv.h:
Added new GLOBAL variable timed_mutexes
ha_innodb.h:
New function innodb_mutex_show_status
ha_innodb.cc:
Added new innodb variables in SHOW STATUS
Implements the SHOW MUTEX STATUS command
innodb.test, innodb.result:
Added new row_lock_waits status variables tests.
variables.test, variables.result:
test new variable timed_mutexes
ut0ut.c:
New function ut_usectime.
sync0sync.c:
Mutex counting.
sync0rw.c:
New mutex parameters initialization.
srv0srv.c:
Counting row lock waits
row0sel.c, row0mysql.c:
Setting row_lock or table_lock state to thd.
que0que.c:
Added default no_lock_state to thd.
univ.i:
Added UNIV_SRV_PRINT_LATCH_WAITS debug define
sync0sync.ic:
Count mutex using.
sync0sync.h:
Added new parameters to mutex structure for counting.
sync0rw.h:
Added new parameters to rw_create_func.
srv0srv.h:
Added new innodb varuables to SHOW STATUS.
que0que.h:
Added thread lock states.
Changed my_error() to print error messages, which come from
arbitrary registered ranges of error messages. Messages can
be unregistered (and should be at end of the program).
Added registration of handler error messages.
Added a new mi_print_error() macro and a new
mi_report_error() function, which supply error
messages with a table name.
Added calls to mi_print_error() or mi_report_error()
at all places in MyISAM, where table corruption is detected.
to behave well on 5.0 tables (well now you can't use tables from 4.1
and 5.0 with 4.0 because former use utf8, but still it is nice to have
similar code in acl_init() and replace_user_table()).
This also will make such GRANTs working in 5.0 (they are broken now).
STR_TO_DATE() function if there is another format specifier after %f
in format string". Also small cleanup of STR_TO_DATE() implementation.
(After review version.)
