- Fix valgrind warning on attempt to run a "SET optimizer_switch=number" statement.
Need to call c_ptr_safe() as strings returned by non-string items are not
necessarily null-terminated.
select where .. (col=col and col=col) or ... (false expression)
Problem: optimizer didn't take into account a singular case
when we eliminated all the predicates at the AND level of WHERE.
That may lead to wrong results.
Fix: replace (a=a AND a=a...) with TRUE if we eliminated all the
predicates.
The problem is that creating a event could fail if the value of
the variable server_id didn't fit in the originator column of
the event system table. The cause is two-fold: it was possible
to set server_id to a value outside the documented range (from
0 to 2^32-1) and the originator column of the event table didn't
have enough room for values in this range.
The log tables (general_log and slow_log) also don't have a proper
column type to store the server_id and having a large server_id
value could prevent queries from being logged.
The solution is to ensure that all system tables that store the
server_id value have a proper column type (int unsigned) and that
the variable can't be set to a value that is not within the range.
The copy of the original arguments of a aggregate function was not
initialized until after fix_fields().
Sometimes (e.g. when there's an error processing the statement)
the print() can be called with no corresponding fix_fields() call.
Fixed by adding a check if the Item is fixed before using the arguments
copy.
Took the Xfree implementation (based on the same rewrite as the NDB one)
and added it instead of the current implementation.
Added a macro to make the calls to MD5 more streamlined.
This is a back port from 5.1 to 5.0.
Fix for BUG 20023: mysql_change_user() resets the value
of SQL_BIG_SELECTS.
The bug was that SQL_BIG_SELECTS was not properly set
in COM_CHANGE_USER.
The fix is to update SQL_BIG_SELECTS properly.
The problem was that the server was trying to use the unknown
error format string (ER_UNKNOWN_ERROR) to print messages about
comments being too long, but the said format string does not
accept arguments and will always default to "Unknown error".
The solution is to introduce new error messages which are
specific to the error conditions so that server wants to
signal -- this also means that it's possible to translate
those messages.
When using mixed mode the record values stored inside the storage
engine differed from the ones computed from the row event. This
happened because the prepare_record function was calling
empty_record macro causing some don't care bits to be left set.
Replacing the empty_record plus explicitly setting defaults with
restore_record to restore the record default values fixes this.
An unnecessarily restrictive lock were taken on sub-SELECTs during DELETE.
During parsing, a global structure is reused for sub-SELECTs and the attribute
keeping track of lock options were not reset properly.
This patch introduces a new attribute to keep track on the syntactical lock
option elements found in a sub-SELECT and then sets the lock options accordingly.
Now the sub-SELECTs will try to acquire a READ lock if possible
instead of a WRITE lock as inherited from the outer DELETE statement.
When binlog_format is STATEMENT and the statement is unsafe before,
the unsafe warning/error message was issued without checking
whether the SQL_LOG_BIN was turned on or not.
Fixed with adding a sql_log_bin_toplevel flag in THD to check
whether SQL_LOG_BIN is ON in current session whatever the current is in sp or not.
The query cache module did not check for the SQL_NO_CACHE keyword before
attempting to query the hash lookup table. This had a small performance impact.
By introducing a check on the query string before obtaining the hash mutex
we can gain some performance if the SQL_NO_CACHE directive is used often.
The problem here seem to be that when mysql
is redirecting stderr to a file, stderr becomes
buffered, whereas it is unbuffered by definition.
The solution is to unbuffer it by setting buffer
to null.
Bug #18828: If InnoDB runs out of undo slots, it returns misleading 'table is full'
This is a backport of code already in 5.1+. The error message change referred
to in the detailed revision comments is still pending.
Detailed revision comments:
r3937 | calvin | 2009-01-15 03:11:56 +0200 (Thu, 15 Jan 2009) | 17 lines
branches/5.0:
Backport the fix for Bug#18828. Return DB_TOO_MANY_CONCURRENT_TRXS
when we run out of UNDO slots in the rollback segment. The backport
is requested by MySQL under bug#41529 - Safe handling of InnoDB running
out of undo log slots.
This is a partial fix since the MySQL error code requested to properly
report the error condition back to the client has not yet materialized.
Currently we have #ifdef'd the error code translation in ha_innodb.cc.
This will have to be changed as and when MySQl add the new requested
code or an equivalent code that we can then use.
Given the above, currently we will get the old behavior, not the
"fixed" and intended behavior.
Approved by: Heikki (on IM)
Set wrong sql_mode when creating a procedure.
So that the sql_mode can't be writen into binary log correctly.
Restore the current session sql_mode right before generating the binlog event
when creating a procedure.
return no rows
The algorithm of determining the best key for loose index scan is doing a loop
over the available indexes and selects the one that has the best cost.
It retrieves the parameters of the current index into a set of variables.
If the cost of using the current index is lower than the best cost so far it
copies these variables into another set of variables that contain the
information for the best index so far.
After having checked all the indexes it uses these variables (outside of the
index loop) to create the table read plan object instance.
The was a single omission : the key_infix/key_infix_len variables were used
outside of the loop without being preserved in the loop for the best index
so far.
This causes these variables to get overwritten by the next index(es) checked.
Fixed by adding variables to hold the data for the current index, passing
the new variables to the function that assigns values to them and copying
the new variables into the existing ones when selecting a new current best
index.
To avoid further such problems moved the declarations of the variables used
to keep information about the current index inside the loop's compound
statement.
