The problem was caused by the following scenario:
- range optimizer picks an index IDX1 which doesn't match the ORDER BY ...
LIMIT clause.
- test_if_skip_sort_order() decides to switch to index IDX2 which matches
the ORDER BY ... LIMIT.
- it runs SQL_SELECT::test_quick_select() for the second time to produce
an quick select for IDX2.
- However, test_quick_select() would figure that full index scan on IDX1
is still cheaper (its calculations ignore the LIMIT n).
Fixed this by
- passing force_quick_range=true to test_quick_select()
- in test_quick_select, don't consider full index scans if the mentioned
parameter is true.
Numerous changes in .result files are caused by test_quick_select() being
run after "early/late NULLs filtering" feature has injected NOT NULL
condition.
MDEV-6656: Test wsrep.variables hangs
Analysis: wsrep_applier_thread shutdown signaling does not always work
correctly causing a timing problem where main thread is waiting in a
condition variable a signal that all worker threads to end.
Merged lp:maria/maria-10.0-galera up to revision 3880.
Added a new functions to handler API to forcefully abort_transaction,
producing fake_trx_id, get_checkpoint and set_checkpoint for XA. These
were added for future possiblity to add more storage engines that
could use galera replication.
Merged lp:maria/maria-10.0-galera up to revision 3879.
Added a new functions to handler API to forcefully abort_transaction,
producing fake_trx_id, get_checkpoint and set_checkpoint for XA. These
were added for future possiblity to add more storage engines that
could use galera replication.
Added a new functions to handler API to forcefully abort_transaction,
producing fake_trx_id, get_checkpoint and set_checkpoint for XA. These
were added for future possiblity to add more storage engines that
could use galera replication.
IS [NOT] NULL predicate is sargable within an outer join. Range
analysis only uses predicates from ON expressions, which have
regular semantics (without null-complemented rows, etc).
There is no reason not use IS [NOT] NULL predicates.
- After PREPARE is done, save the value of thd->select_number
(this is what will be assigned to next select_lex object)
- Restore the value at each execution of the prepared statement.
mysqldump:
- Added --log-queries to allow one to disable logging for the dump
sql/log_event.cc:
- Removed setting of enable_slow_log as it's not required anymore.
sql/sql_parse.cc:
- Set enable_slow_log to value of thd->variables.sql_log_slow as this will speed up tests if slow log is disabled.
- opt_log_slow_admin_statements can now only disable slow log, not enable it.
sql/sql_explain.cc:
- Minor cleanup
Other things:
- Added sql_log_slow to system variables.
- Changed opt_slow_log to global_system_variables.sql_log_slow in all files
- Updated tests to reflect changes
buf0buf.cc line 2642.
Analysis: innodb_compression_algorithm is a global variable and
can change while we are building page compressed page. This could
lead page corruption.
Fix: Cache innodb_compression_algorithm on local variable before
doing any compression or page formating to avoid concurrent
change. Improved page verification on debug builds.
Analysis: InnoDB writes also files that do not contain FIL-header.
This could lead incorrect analysis on os_fil_read_func function
when it tries to see is page page compressed based on FIL_PAGE_TYPE
field on FIL-header. With bad luck uncompressed page that does
not contain FIL-headed, the byte on FIL_PAGE_TYPE position could
indicate that page is page comrpessed.
Fix: Upper layer must indicate is file space page compressed
or not. If this is not yet known, we need to read the FIL-header
and find it out. Files that we know that are not page compressed
we can always just provide FALSE.