The cause of regression was handling for ROWNUM() function.
For queries like
SELECT ROWNUM() FROM ... ORDER BY ...
ROWNUM() should be computed before the ORDER BY.
The computation was moved to be before the ORDER BY for any entries in
the select list that had RAND_TABLE_BIT set.
This had a negative impact on queries in form:
SELECT sp_func() FROM t1 ORDER BY ... LIMIT n
where sp_func() is NOT declared as DETERMINISTIC (and so has
RAND_TABLE_BIT set).
The fix is to require evaluation for sorting only for the ROWNUM()
function. Functions that just have RAND_TABLE_BIT() can be computed
after ORDER BY ... LIMIT is applied.
(think about a possible index that satisfies the ORDER BY clause. In
that case, the the rows would be read in the needed order and we would
stop after reading LIMIT rows, achieving the same effect).
Some SQL statements that involves subqueries or stored routines could
fail since execution of subqueries or stored routines is not supported
for theses statements. Unfortunately, parsing error could result in
abnormal termination by firing the following assert
DBUG_ASSERT(m_thd == NULL);
in a destructor of the class sp_head.
The reason of the assert firing is that the method
sp_head::restore_thd_mem_root()
is not called on semantic action code to clean up resources allocated
during parsing. This happens since the macros YYABORT is called instead of
MYSQL_YYABORT by semantic action code for some grammar rules.
So, to fix the bug YYABORT was just replaced with MYSQL_YYABORT.
This bug report is about the same issue as MDEV-28129 and MDEV-21173.
The issue is that the macros YYABORT is called instead of MYSQL_YYABORT
on parse error. In result the method LEX::cleanup_lex_after_parse_error
is not called to clean up data structures created on parsing of
the statement.
The reason for this behavior is that SP get cached, per connection.
The stored_program_cache is size of this cache, which amounts to 256
routines by default. A compiled stored procedure can easily be several
megabytes in size. Thus calling SHOW CREATE PROCEDURE for all stored
procedures, like mysqldump does, can require significant amount of memory.
Fixed by bypassing the cache for "SHOW CREATE". This should normally be
fine also perfomance-wise, as cache is meant to be used for repeated
execution, not repeated SHOW CREATEs.
Added a test to verify that CREATE PROCEDURE + SHOW CREATE PROCEURE do not
cache, i.e amount of allocated memory does not change.
Note, there is a change in existing behavior in an edge case :
If "SHOW CREATE PROCEDURE p1" called from p1, after p1 was altered, now
this will now return altered code. Previour behavior - relied on caching
and would return old code. The previous behavior might was not necessarily
correct.
This patch changes the main name of 3 byte character set from utf8 to
utf8mb3. New old_mode UTF8_IS_UTF8MB3 is added and set TRUE by default,
so that utf8 would mean utf8mb3. If not set, utf8 would mean utf8mb4.
Also increase user name up to 128.
The work was started by Rucha Deodhar <rucha.deodhar@mariadb.com>,
contains audit plugin fixes by Alexey Botchkov <holyfoot@askmonty.org>.
This feature adds the functionality of ignorability for indexes.
Indexes are not ignored be default.
To control index ignorability explicitly for a new index,
use IGNORE or NOT IGNORE as part of the index definition for
CREATE TABLE, CREATE INDEX, or ALTER TABLE.
Primary keys (explicit or implicit) cannot be made ignorable.
The table INFORMATION_SCHEMA.STATISTICS get a new column named IGNORED that
would store whether an index needs to be ignored or not.
- IF EXISTS ends with a list of all not existing object, instead of a
separate note for every not existing object
- Produce a "Note" for all wrongly dropped objects
(like trying to do DROP SEQUENCE for a normal table)
- Do not write existing tables that could not be dropped to binlog
Other things:
MDEV-22820 Bogus "Unknown table" warnings produced upon attempt to drop
parent table referenced by FK
This was caused by an older version of this commit patch and later fixed
In main.index_merge_myisam we remove the test that was added in
commit a2d24def8c because
it duplicates the test case that was added in
commit 5af12e4635.
