The problem is that one can not create a stored routine if sql_mode
contains NO_ENGINE_SUBSTITUTION or PAD_CHAR_TO_FULL_LENGTH. Also when
a event is created, the mode is silently lost if sql_mode contains one
of the aforementioned. This was happening because the table definitions
which stored sql_mode values weren't being updated to accept new values
of sql_mode.
The solution is to update, in a backwards compatible manner, the various
table definitions (columns) that store the sql_mode value to take into
account the new possible values. One incompatible change is that if a event
that is being created can't be stored to the mysql.event table, an error
will be raised.
The tests case also ensure that new SQL modes will be added to the mysql.proc
and mysql.event tables, otherwise the tests will fail.
Simple subselects are pulled into upper selects. This operation substitutes the
pulled subselect for the first item from the select list of the subselect.
If an alias is defined for a subselect it is inherited by the replacement item.
As this is done after fix_fields phase this alias isn't showed if the
replacement item is a stored function. This happens because the Item_func_sp::make_field
function makes send field from its result_field and ignores the defined alias.
Now when an alias is defined the Item_func_sp::make_field function sets it for
the returned field.
The problem was that the RETURNS column in the mysql.proc was of
CHAR(64). That was not enough for storing long-named datatypes.
The fix is to change CHAR(64) to LONGBLOB, and to throw warnings
at the time a stored routine is created if some data is truncated
during writing into mysql.proc.
when used in a VIEW.
The problem was that wrong function (create_tmp_from_item())
was used to create a temporary field for Item_func_sp.
The fix is to use create_tmp_from_field().
This actually, fix for the patch for bug-27354. The problem with
the patch was that Item_func_sp::used_tables() was updated, but
Item_func_sp::const_item() was not. So, for Item_func_sp, we had
the following inconsistency:
- used_tables() returned RAND_TABLE, which means that the item
can produce "random" results;
- but const_item() returned TRUE, which means that the item is
a constant one.
The fix is to change Item_func_sp::const_item() behaviour: it must
return TRUE (an item is a constant one) only if a stored function
is deterministic and each of its arguments (if any) is a constant
item.
SP with local variables with non-ASCII names crashed the server.
The server replaces SP local variable names with NAME_CONST calls
when putting statements into the binary log. It used UTF8-encoded
item names as variable names for the replacement inside NAME_CONST
calls. However, statement string may be encoded by any
known character set by the SET NAMES statement.
The server used byte length of UTF8-encoded names to increment
the position in the query string that led to array index overrun.
Optimization of queries with DETERMINISTIC functions in the
WHERE clause was not effective: sequential scan was always
used.
Now a SF with the DETERMINISTIC flags is treated as constant
when it's arguments are constants (or a SF doesn't has arguments).
fails if a database is not selected prior.
The problem manifested itself when a user tried to
create a routine that had non-fully-qualified identifiers in its bodies
and there was no current database selected.
This is a regression introduced by the fix for Bug 19022:
The patch for Bug 19022 changes the code to always produce a warning
if we can't resolve the current database in the parser.
In this case this was not necessary, since even though the produced
parsed tree was incorrect, we never re-use sphead
that was obtained at first parsing of CREATE PROCEDURE.
The sphead that is anyhow used is always obtained through db_load_routine,
and there we change the current database to sphead->m_db before
calling yyparse.
The idea of the fix is to resolve the current database directly using
lex->sphead->m_db member when parsing a stored routine body, when
such is present.
This patch removes the need to reset the current database
when loading a trigger or routine definition into SP cache.
The redundant code will be removed in 5.1.
'No database selected' is reported when calling stored procedures
Remove the offending warning introduced by the fix for Bug
25082
This minimal patch relies on the intrinsic knowledge of the fact that
mysql_change_db is never called with 'force_switch' set to TRUE
when such a warning may be needed:
* every stored routine belongs to a database (unlike, e.g., a
user defined function, which does not), so if we're activating the
database of a stored routine, it can never be NULL.
Therefore, this branch is never called for activation.
* if we're restoring the 'old' current database after routine
execution is complete, we should not issue a warning, since it's OK to
call a routine without having previously selected the current database.
TODO: 'force_switch' is an ambiguous flag, since we do not actually
have to 'force' the switch in case of stored routines at all.
When we activate the routine's database, we should perform
all the checks as in case of 'use db', and so we already do (in this
case 'force_switch' is unused).
When we load a routine into cache, we should not use mysql_change_db
at all, since there it's enough to call thd->reset_db(). We
do it this way for triggers, but code for routines is different (wrongly).
TODO: bugs are lurking in replication, since it bypasses mysql_change_db
and calls thd->[re_]set_db to set the current database.
The latter does not change thd->db_charset, thd->sctx->db_access
and thd->variables.collation_database (and this may have nasty side
effects).
These todo items are to be addressed in a separate patch, if at all.
- BUG#11986: Stored routines and triggers can fail if the code
has a non-ascii symbol
- BUG#16291: mysqldump corrupts string-constants with non-ascii-chars
- BUG#19443: INFORMATION_SCHEMA does not support charsets properly
- BUG#21249: Character set of SP-var can be ignored
- BUG#25212: Character set of string constant is ignored (stored routines)
- BUG#25221: Character set of string constant is ignored (triggers)
There were a few general problems that caused these bugs:
1. Character set information of the original (definition) query for views,
triggers, stored routines and events was lost.
2. mysqldump output query in client character set, which can be
inappropriate to encode definition-query.
3. INFORMATION_SCHEMA used strings with mixed encodings to display object
definition;
1. No query-definition-character set.
In order to compile query into execution code, some extra data (such as
environment variables or the database character set) is used. The problem
here was that this context was not preserved. So, on the next load it can
differ from the original one, thus the result will be different.
The context contains the following data:
- client character set;
- connection collation (character set and collation);
- collation of the owner database;
The fix is to store this context and use it each time we parse (compile)
and execute the object (stored routine, trigger, ...).
2. Wrong mysqldump-output.
The original query can contain several encodings (by means of character set
introducers). The problem here was that we tried to convert original query
to the mysqldump-client character set.
Moreover, we stored queries in different character sets for different
objects (views, for one, used UTF8, triggers used original character set).
The solution is
- to store definition queries in the original character set;
- to change SHOW CREATE statement to output definition query in the
binary character set (i.e. without any conversion);
- introduce SHOW CREATE TRIGGER statement;
- to dump special statements to switch the context to the original one
before dumping and restore it afterwards.
Note, in order to preserve the database collation at the creation time,
additional ALTER DATABASE might be used (to temporary switch the database
collation back to the original value). In this case, ALTER DATABASE
privilege will be required. This is a backward-incompatible change.
3. INFORMATION_SCHEMA showed non-UTF8 strings
The fix is to generate UTF8-query during the parsing, store it in the object
and show it in the INFORMATION_SCHEMA.
Basically, the idea is to create a copy of the original query convert it to
UTF8. Character set introducers are removed and all text literals are
converted to UTF8.
This UTF8 query is intended to provide user-readable output. It must not be
used to recreate the object. Specialized SHOW CREATE statements should be
used for this.
The reason for this limitation is the following: the original query can
contain symbols from several character sets (by means of character set
introducers).
Example:
- original query:
CREATE VIEW v1 AS SELECT _cp1251 'Hello' AS c1;
- UTF8 query (for INFORMATION_SCHEMA):
CREATE VIEW v1 AS SELECT 'Hello' AS c1;