account predicates that become sargable after reading const tables.
In some cases this resulted in choosing non-optimal execution plans.
Now info of such potentially saragable predicates is saved in
an array and after reading const tables we check whether this
predicates has become saragable.
Presence of a subquery in the ON expression of a join
should not block merging the view that contains this join.
Before this patch the such views were converted into
into temporary table views.
containing a select statement that uses an aggregating IN subquery.
Added a parameter to the function fix_prepare_information
to restore correctly the having clause for the second execution.
Saved andor structure of the having conditions at the proper moment
before any calls of split_sum_func2 that could modify the having structure
adding new Item_ref objects. (These additions, are produced not with
the statement mem_root, but rather with the execution mem_root.)
make st_select_lex::setup_ref_array() take into account that
Item_sum-descendant objects located within descendant SELECTs
may be added into ref_pointer_array.
handle them.
Problem:
CREATE|ALTER EVENT, HANDLER READ, KILL, Partitioning uses `expr` from the
parser. This rule comes with all the rings and bells including subqueries.
However, these commands are not subquery safe. For this reason there are two
fuse checks in the parser. They were checking by command id. CREATE EVENT
should forbid subquery is the fix for
bug#16394 Events: Crash if schedule contains SELECT
The fix has been incorporated as part of the patch for WL#3337 (Event scheduler
new architecture).
Solution:
A new flag was added to LEX command_forbids_subselect. The fuse checks were
changed. The commands are responsible to set the value to true whenever
they can't handle subselects.
Zero-length variables caused failures when using the length to look
up the name in a hash. Instead, signal that no zero-length name can
ever be found and that to encounter one is a syntax error.
- if there are two character set definitions in the column declaration,
we replace the first one with the second one as we store both in the LEX->charset
slot. Add a separate slot to the LEX structure to store underscore charset.
- convert default values to the column charset of STRING, VARSTRING fields
if necessary as well.
can be not replicable.
Now CREATE statements for writing in the binlog are created as follows:
- the beginning of the statement is re-created;
- the rest of the statement is copied from the original query.
The problem appears when there is a version-specific comment (produced by
mysqldump), started in the re-created part of the statement and closed in the
copied part -- there is closing comment-parenthesis, but there is no opening
one.
The proper fix could be to re-create original statement, but we can not
implement it in 5.0. So, for 5.0 the fix is just to cut closing
comment-parenthesis. This technique is also used for SHOW CREATE PROCEDURE
statement (so we are able to reuse existing code).
1) Fix for BUG#19630 "stored function inserting into two auto_increment breaks
statement-based binlog":
a stored function inserting into two such tables may fail to replicate
(inserting wrong data in the slave's copy of the second table) if the slave's
second table had an internal auto_increment counter different from master's.
Because the auto_increment value autogenerated by master for the 2nd table
does not go into binlog, only the first does, so the slave lacks information.
To fix this, if running in mixed binlogging mode, if the stored function or
trigger plans to update two different tables both having auto_increment
columns, we switch to row-based for the whole function.
We don't have a simple solution for statement-based binlogging mode, there
the bug remains and will be documented as a known problem.
Re-enabling rpl_switch_stm_row_mixed.
2) Fix for BUG#20630 "Mixed binlogging mode does not work with stored
functions, triggers, views", which was a documented limitation (in mixed
mode, we didn't detect that a stored function's execution needed row-based
binlogging (due to some UUID() call for example); same for
triggers, same for views (a view created from a SELECT UUID(), and doing
INSERT INTO sometable SELECT theview; would not replicate row-based).
This is implemented by, after parsing a routine's body, remembering in sp_head
that this routine needs row-based binlogging. Then when this routine is used,
the caller is marked to require row-based binlogging too.
Same for views: when we parse a view and detect that its SELECT needs
row-based binary logging, we mark the calling LEX as such.
3) Fix for BUG#20499 "mixed mode with temporary table breaks binlog":
a temporary table containing e.g. UUID has its changes not binlogged,
so any query updating a permanent table with data from the temporary table
will run wrongly on slave. Solution: in mixed mode we don't switch back
from row-based to statement-based when there exists temporary tables.
4) Attempt to test mysqlbinlog on a binlog generated by mysqlbinlog;
impossible due to BUG#11312 and BUG#20329, but test is in place for when
they are fixed.
dropping/creating tables".
The bug could lead to a crash when multi-delete statements were
prepared and used with temporary tables.
The bug was caused by lack of clean-up of multi-delete tables before
re-execution of a prepared statement. In a statement like
DELETE t1 FROM t1, t2 WHERE ... the first table list (t1) is
moved to lex->auxilliary_table_list and excluded from lex->query_tables
or select_lex->tables. Thus it was unaccessible to reinit_stmt_before_use
and not cleaned up before re-execution of a prepared statement.
This cut No 7 should finish the part of fixing the parsing of the events :
- Event_timed is no more used during parsing. Less problems because it has
a mutex. Event_parse_data class is used during parsing. It is suited only
for this purpose. It's pretty lightweight
- Late checking of data from parsing is being performed. This should solve
the problems of nested events in SP or other events (for the situation
of no nested bodies). Before if an ALTER EVENT was in a SP, then when the
SP was compiled, and not executed, the actual init_xxx methods of Event_timed
were called, which is wrong.
- It could be a side effect of using a specialized class, but test events_stress is
now 25% quicker.
Cut No8 will start splitting Event_scheduler into 2 parts, the QUEUE will be moved
to Event_queue.
The problem was that we restored SQL_CACHE, SQL_NO_CACHE flags in SELECT
statement from internal structures based on value set later at runtime, not
the original value set by the user.
The solution is to remember that original value.
SHOW STATUS are not anymore put in slow query log because of no index usage.
Implemntation done by removing orig_sql_command and moving logic of SHOW STATUS to mysql_excute_command()
This simplifies code and allows us to remove some if statements all over the code.
Upgraded uc_update_queries[] to sql_command_flags and added more bitmaps to better categorize commands.
This allowed some overall simplifaction when testing sql_command.
Fixes bugs:
Bug#10210: running SHOW STATUS increments counters it shouldn't
Bug#19764: SHOW commands end up in the slow log as table scans
Old FRM files didn't allow byte 255 as a column name part.
Since now we store column names in UTF8, this restriction
is not required anymore: 255 is not a valid byte in UTF8.
Fix: removing checking against 255.
Bug#18282 "INFORMATION_SCHEMA.TABLES provides inconsistent info about invalid views"
This bug caused crashes or resulted in wrong data being returned
when one tried to obtain information from I_S tables about views
using stored functions.
It was caused by the fact that we were using LEX representing
statement which were doing select from I_S tables as active LEX
when contents of I_S table were built. So state of this LEX both
affected and was affected by open_tables() calls which happened
during this process. This resulted in wrong behavior and in
violations of some of invariants which caused crashes.
This fix tries to solve this problem by properly saving/resetting
and restoring part of LEX which affects and is affected by the
process of opening tables and views in get_all_tables() routine.
To simplify things we separated this part of LEX in a new class
and made LEX its descendant.
