- When a shared library argument is supplied, it's checked for an OS
specific directory separator. The expected error is different
depending on the separator used. Created OS specific versions of these
tests.
Before this change, the functions BENCHMARK, ENCODE, DECODE and FORMAT could
only accept a constant for some parameters.
After this change, this restriction has been removed. An implication is that
these functions can also be used in prepared statements.
The change consist of changing the following classes:
- Item_func_benchmark
- Item_func_encode
- Item_func_decode
- Item_func_format
to:
- only accept Item* in the constructor,
- and evaluate arguments during calls to val_xxx()
which fits the general design of all the other functions.
The 'TODO' items identified in item_create.cc during the work done for
Bug 21114 are addressed by this fix, as a natural consequence of aligning
the design.
In the 'func_str' test, a single very long test line involving an explain
extended select with many functions has been rewritten into multiple
separate tests, to improve maintainability.
The result of explain extended select decode(encode(...)) has changed,
since the encode and decode functions now print all their parameters.
When statement to be prepared contained CREATE PROCEDURE, CREATE FUNCTION
or CREATE TRIGGER statements with a syntax error in it, the preparation
would fail with syntax error message, but the memory could be corrupted.
The problem occurred because we switch memroot when parse stored
routine or trigger definitions, and on parse error we restored the
original memroot only after performing some memory operations. In more
detail:
- prepared statement would activate its own memory root to parse
the definition of the stored procedure.
- SP would reset this memory root with its own memory root to
parse SP statements
- a syntax error would happen
- prepared statement would restore the original memory root
- stored procedure would restore what it thinks was the original
memory root, but actually was the statement memory root.
That led to double free - in destruction of the statement and in
a next call to mysql_parse().
The solution is to restore memroot right after the failed parsing.
Do not consider SHOW commands slow queries, just because they don't use proper indexes.
This bug fix is not needed in 5.1, and the code changes will be null merged. However, the test cases will be propogated up to 5.1.
statement.
The problem was that during statement re-execution if the result was
empty the old result could be returned for group functions.
The solution is to implement proper cleanup() method in group
functions.
Re-execution of a parametrized prepared statement or a stored routine
with a SELECT that use LEFT JOIN with second table having only one row
could yield incorrect result.
The problem appeared only for left joins with second table having only
one row (aka const table) and equation conditions in ON or WHERE clauses
that depend on the argument passed. Once the condition was false for
second const table, a NULL row was created for it, and any field involved
got NULL-value flag, which then was never reset.
The cause of the problem was that Item_field::null_value could be set
without being reset for re-execution. The solution is to reset
Item_field::null_value in Item_field::cleanup().
statement that uses an aggregating IN subquery with
HAVING clause.
A wrong order of the call of split_sum_func2 for the HAVING
clause of the subquery and the transformation for the
subquery resulted in the creation of a andor structure
that could not be restored at an execution of the prepared
statement.
should work in Prepared Statements. Post-review changeset.
Problem: There are some commands which are avaiable to be executed in SP
but cannot be prepared. This patch fixes this and makes it possible
prepare these statements.
Changes: The commands later are made available in PS. RESET has been forbidden
in SF/Trigger.
Solution: All current server commands where checked and those missing (see later)
we added. Tests for all of the commands with repeated executions were
added - testing with SP, SF and PS.
SHOW BINLOG EVENTS
SHOW (MASTER | SLAVE) STATUS
SHOW (MASTER | BINARY) LOGS
SHOW (PROCEDURE | FUNCTION) CODE (parsable only in debug builds)
SHOW CREATE (PROCEDURE | FUNCTION | EVENT | TABLE | VIEW)
SHOW (AUTHORS | CONTRIBUTORS | WARNINGS | ERRORS)
CHANGE MASTER
RESET (MASTER | SLAVE | QUERY CACHE)
SLAVE (START | STOP)
CHECKSUM (TABLE | TABLES)
INSTALL PLUGIN
UNINSTALL PLUGIN
CACHE INDEX
LOAD INDEX INTO CACHE
GRANT
REVOKE
KILL
(CREATE | RENAME | DROP) DATABASE
(CREATE | RENAME | DROP) USER
FLUSH (TABLE | TABLES | TABLES WITH READ LOCK | HOSTS | PRIVILEGES |
LOGS | STATUS | MASTER | SLAVE | DES_KEY_FILE | USER_RESOURCES)
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.
Bug#19022 "Memory bug when switching db during trigger execution"
Bug#17199 "Problem when view calls function from another database."
Bug#18444 "Fully qualified stored function names don't work correctly in
SELECT statements"
Documentation note: this patch introduces a change in behaviour of prepared
statements.
This patch adds a few new invariants with regard to how THD::db should
be used. These invariants should be preserved in future:
- one should never refer to THD::db by pointer and always make a deep copy
(strmake, strdup)
- one should never compare two databases by pointer, but use strncmp or
my_strncasecmp
- TABLE_LIST object table->db should be always initialized in the parser or
by creator of the object.
For prepared statements it means that if the current database is changed
after a statement is prepared, the database that was current at prepare
remains active. This also means that you can not prepare a statement that
implicitly refers to the current database if the latter is not set.
This is not documented, and therefore needs documentation. This is NOT a
change in behavior for almost all SQL statements except:
- ALTER TABLE t1 RENAME t2
- OPTIMIZE TABLE t1
- ANALYZE TABLE t1
- TRUNCATE TABLE t1 --
until this patch t1 or t2 could be evaluated at the first execution of
prepared statement.
CURRENT_DATABASE() still works OK and is evaluated at every execution
of prepared statement.
Note, that in stored routines this is not an issue as the default
database is the database of the stored procedure and "use" statement
is prohibited in stored routines.
This patch makes obsolete the use of check_db_used (it was never used in the
old code too) and all other places that check for table->db and assign it
from THD::db if it's NULL, except the parser.
How this patch was created: THD::{db,db_length} were replaced with a
LEX_STRING, THD::db. All the places that refer to THD::{db,db_length} were
manually checked and:
- if the place uses thd->db by pointer, it was fixed to make a deep copy
- if a place compared two db pointers, it was fixed to compare them by value
(via strcmp/my_strcasecmp, whatever was approproate)
Then this intermediate patch was used to write a smaller patch that does the
same thing but without a rename.
TODO in 5.1:
- remove check_db_used
- deploy THD::set_db in mysql_change_db
See also comments to individual files.
