min() and max() functions are implemented in MySQL as macros.
This means that max(a,b) is expanded to: ((a) > (b) ? (a) : (b))
Note how 'a' is quoted two times.
Now imagine 'a' is a recursive function call that's several 10s of levels deep.
And the recursive function does max() with a function arg as well to dive into
recursion.
This means that simple function call can take most of the clock time.
Identified and fixed several such calls to max()/min() : including the IF()
sql function implementation.
mysql-test/r/func_if.result:
Bug#37662 test case
mysql-test/t/func_if.test:
Bug#37662 test case
sql/item.cc:
Bug#37662 don't call expensive functions as arguments to min/max
sql/item_cmpfunc.cc:
Bug#37662 don't call expensive functions as arguments to min/max
sql/item_func.cc:
Bug#37662 don't call expensive functions as arguments to min/max
Post-push fix: updated some result files that were affected
by the previous fix to this bug.
mysql-test/suite/binlog/r/binlog_killed_simulate.result:
Updated result file.
mysql-test/suite/binlog/r/binlog_row_binlog.result:
Updated result file.
mysql-test/suite/binlog/r/binlog_row_mix_innodb_myisam.result:
Updated result file.
mysql-test/suite/binlog/r/binlog_statement_insert_delayed.result:
Updated result file.
mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result:
Updated result file.
mysql-test/suite/rpl/r/rpl_stm_log.result:
Updated result file.
Calling List<Cached_item>::delete_elements for the same list twice
caused a crash of the server in the function JOIN::cleaunup.
Ensured that delete_elements() in JOIN::cleanup would be called only once.
mysql-test/r/subselect.result:
Added a test case for bug #38191.
mysql-test/t/subselect.test:
Added a test case for bug #38191.
sql/sql_select.cc:
Fixed bug #38191.
Ensured that delete_elements() in JOIN::cleanup would be called only once.
Tables in the table definition cache are keeping a cache buffer for blob
fields which can consume a lot of memory.
This patch introduces a maximum size threshold for these buffers.
sql/sql_base.cc:
Added function free_field_buffers_larger_than to reclaim memory from blob
field buffers too large to be cached.
sql/table.cc:
Added function free_field_buffers_larger_than
Problem: binlog_stm_binlog runs INSERT DELAYED queries, and
then prints the contents of the binlog. Before checking the
contents of the binlog, the test waits until the rows have
appeared in the table. However, this is not enough, since
INSERT DELAYED does not write rows to the binlog at the same
time as it writes them to the table. So there is a race.
Fix: Add a FLUSH TABLES before SHOW BINLOG EVENTS. That
waits until the insert_delayed thread is done.
mysql-test/extra/binlog_tests/binlog_insert_delayed.test:
- Added FLUSH TABLES, so that SHOW BINLOG EVENTS becomes
deterministic.
- Added comments.
- Removed unnecessary 'set @@session.auto_increment_increment'
statements.
- Removed unnecessary check that the number of rows inserted
to the table is 11.
mysql-test/suite/binlog/r/binlog_stm_binlog.result:
updated result file
BUG#37884: rpl_row_basic_2myisam and rpl_row_basic_3innodb fail sporadically in pushbuild
These have been fixed in 5.1-rpl. Re-applying fix for BUG#37884
in 5.1-bugteam, and disabling rpl_flushlog_loop for BUG#37733 in
5.1-bugteam.
mysql-test/extra/rpl_tests/rpl_row_basic.test:
Missing sync_slave_with_master added.
mysql-test/suite/rpl/t/disabled.def:
Disabling rpl_flushlog_loop until the fixed version gets
merged from 5.1-rpl
Range scan in descending order for c <= <col> <= c type of
ranges was ignoring the DESC flag.
However some engines like InnoDB have the primary key parts
as a suffix for every secondary key.
When such primary key suffix is used for ordering ignoring
the DESC is not valid.
But we generally would like to do this because it's faster.
Fixed by performing only reverse scan if the primary key is used.
Removed some dead code in the process.
mysql-test/r/innodb_mysql.result:
Bug#37830 : test case
mysql-test/t/innodb_mysql.test:
Bug#37830 : test case
sql/opt_range.cc:
Bug#37830 :
- preserve and use used_key_parts to
distinguish when a primary key suffix is used
- removed some dead code
sql/opt_range.h:
Bug#37830 :
- preserve used_key_parts
- dead code removed
sql/sql_select.cc:
Bug#37830 : Do only reverse order traversal
if the primary key suffix is used.
Problem: the test waits for a 'DROP TEMPORARY TABLE' event to
appear in the master's binlog, then checks on the slave whether
the number of temporary tables has decreased. The slave does
not sync, causing a race.
Fix: check for the 'DROP TEMPORARY TABLE' event on slave
instead of on master.
mysql-test/suite/rpl/t/rpl_trunc_temp.test:
- Fixed BUG#37493 by waiting for the event on the slave
instead of on the master.
- Added comments.
If the server failed to expired log files during start up it could crash.
sql/log.cc:
Added predicate to protect againt cases when current_thd might be NULL.
