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.
internal charset to one associated with currently being handled query.
To note such a query can come from interactive client either.
There was a discussion within replication team and Monty who's suggestion won.
It avoids straightforward parsing of all `set' queries that could affect client side
character set.
According to the idea, mysql client does not parse `set' queries but rather cares of
`charset new_cs_name' command.
This command is generated by mysqlbinlog in form of exclaiming comment (Lars' suggestion)
so that enlightened clients like `mysql' knows what to do with it.
Interactive human can switch between many multi-byte charsets during the session
providing the command explicitly.
To note that setting new internal mysql's charset does not
trigger sending any `SET' sql statement to the server.
- Fixed tests
- Optimized new code
- Fixed some unlikely core dumps
- Better bug fixes for:
- #14397 - OPTIMIZE TABLE with an open HANDLER causes a crash
- #14850 (ERROR 1062 when a quering a view using a Group By on a column that can be null
Bad examples of usage of a string with its length fixed.
The incorrect length in the trigger file configuration descriptor
fixed (BUG#14090).
A hook for unknown keys added to the parser to support old .TRG files.
in short we now record whenever the slave I/O thread ignores a master's event because of its server id,
and use this info in the slave SQL thread to advance Exec_master_log_pos. Because if we
do not, this variable stays at the position of the last executed event, i.e. the last *non-ignored*
executed one, which may not be the last of the master's binlog (and so the slave *looks* behind
the master though it's data-wise it's not).
- CHAR() now returns binary string as default
- CHAR(X*65536+Y*256+Z) is now equal to CHAR(X,Y,Z) independent of the character set for CHAR()
- Test for both ETIMEDOUT and ETIME from pthread_cond_timedwait()
(Some old systems returns ETIME and it's safer to test for both values
than to try to write a wrapper for each old system)
- Fixed new introduced bug in NOT BETWEEN X and X
- Ensure we call commit_by_xid or rollback_by_xid for all engines, even if one engine has failed
- Use octet2hex() for all conversion of string to hex
- Simplify and optimize code
Ensure that ccache is also used for C programs
mysql: Ensure that 'delimiter' works the same way in batch mode as in normal mode
mysqldump: Change to use ;; (instead of //) as a stored procedure/trigger delimiter
Fixed test cases by adding missing DROP's and rename views to be of type 'v#'
Removed MY_UNIX_PATH from fn_format()
Removed current_db_used from TABLE_LIST
Removed usage of 'current_thd' in Item_splocal
Removed some compiler warnings
A bit faster longlong2str code
Ensure that 'null_value' is not accessed before val() is called in FIELD() functions
Fixed initialization of key maps. This fixes some problems with keys when you have more than 64 keys
Fixed that ROLLUP don't always create a temporary table. This fix ensures that func_gconcat.test results are now predictable
