Fine-tuning. Broke out comparison into method by
suggestion of Davi. Clarified comments. Reverting
test-case which I find too brittle; proper test
case in 5.1+.
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.
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.
Problem: storing "SELECT ... INTO @var ..." results in variables we used val_xxx()
methods which returned results of the current row.
So, in some cases (e.g. SELECT DISTINCT, GROUP BY or HAVING) we got data
from the first row of a new group (where we evaluate a clause) instead of
data from the last row of the previous group.
Fix: use val_xxx_result() counterparts to get proper results.
date_format functions
String::realloc() did not check whether the existing string data fits in
the newly allocated buffer for cases when reallocating a String object
with external buffer (i.e.alloced == FALSE). This could lead to memory
overruns in some cases.
The problem is that a unfiltered user query was being passed as
the format string parameter of sql_print_warning which later
performs printf-like formatting, leading to crashes if the user
query contains formatting instructions (ie: %s). Also, it was
using THD::query as the source of the user query, but this
variable is not meaningful in some situations -- in a delayed
insert, it points to the table name.
The solution is to pass the user query as a parameter for the
format string and use the function parameter query_arg as the
source of the user query.
functions
String::realloc() did not check whether the existing string data fits in the newly
allocated buffer for cases when reallocating a String object with external buffer
(i.e.alloced == FALSE). This could lead to memory overruns in some cases.
The function thd_security_context allocates memory on an unprotected MEM_ROOT if the
message length becomes longer than requested and the initial buffer memory needs to
be reallocated.
This patch fixes the design error by copying parts of the reallocated buffer
to the destination buffer. This works because the destination buffer isn't
owned by the String object and thus isn't freed when a new buffer is allocated.
Any new memory allocated by the String object is reclaimed when the object
is destroyed at the end of the function call.
Innodb monitor could cause a server crash because of invalid access to a
shared variable in a concurrent environment.
This patch adds a guard to protect against crashes but not against
inconsistent values because of performance reasons.
When statement-based replication is used, and the
transaction isolation level is READ-COMMITTED or stricter,
InnoDB will print an error because statement-based
replication might lead to inconsistency between master
and slave databases. However, when the binary log is not
engaged, this is not an issue and an error should
not be printed.
This patch makes thd_binlog_format() return BINLOG_FORMAT_
UNSPEC when the binary log is not engaged for the given
thread.
Debug builds of MySQL 5.1, 6.0 with Sun Studio 12 broke because of
use of gcc specific feature.
The fix is to replace __FUNCTION__ with the corresponding character string
Debug builds of MySQL 5.1, 6.0 with Sun Studio 12 broke because of
use of gcc specific feature.
The fix is to replace __FUNCTION__ with the corresponding character
string
The failure was caused by executing a CREATE-SELECT statement that creates a
table in another database than the current one. In row-based logging, the
CREATE statement was written to the binary log without the database, hence
creating the table in the wrong database, causing the following inserts to
fail since the table didn't exist in the given database.
Fixed the bug by adding a parameter to store_create_info() that will make
the function print the database name before the table name and used that
in the calls that write the CREATE statement to the binary log. The database
name is only printed if it is different than the currently selected database.
The output of SHOW CREATE TABLE has not changed and is still printed without
the database name.
The assertion indicates that some data was left in the transaction
cache when the server was shut down, which means that a previous
statement did not commit or rollback correctly.
What happened was that a bug in the rollback of a transactional
table caused the transaction cache to be emptied, but not reset.
The error can be triggered by having a failing UPDATE or INSERT,
on a transactional table, causing an implicit rollback.
Fixed by always flushing the pending event to reset the state
properly.
The failure was caused by executing a CREATE-SELECT statement that creates a
table in another database than the current one. In row-based logging, the
CREATE statement was written to the binary log without the database, hence
creating the table in the wrong database, causing the following inserts to
fail since the table didn't exist in the given database.
Fixed the bug by adding a parameter to store_create_info() that will make
the function print the database name before the table name and used that
in the calls that write the CREATE statement to the binary log. The database
name is only printed if it is different than the currently selected database.
The output of SHOW CREATE TABLE has not changed and is still printed without
the database name.
The problem of this bug is that we need to get the list of tables
to be updated for a multi-table update statement, which requires to
open all the tables referenced by the statement and resolve all
the fields involved in update in order to figure out the list of
tables for update. However if there are replicate filter rules,
some tables might not exist on slave and result in a failure
before we could examine the filter rules.
I think the whole problem can not be solved on slave alone,
the master must record and send the information of tables
involved for update to slave, so that the slave do not need to
open all the tables referenced by the multi-table update statement to
figure out which tables are involved for update.
So a status variable is added to Query_log event to store the
value of table map for update on master. And on slave, it will
try to get the value of this variable and use it to examine
filter rules without opening any tables on slave, if this values
is not available, the old approach is used and thus the bug will
still occur for when replicating from old masters.
build)
The crash was caused by freeing the internal parser stack during the parser
execution.
This occured only for complex stored procedures, after reallocating the parser
stack using my_yyoverflow(), with the following C call stack:
- MYSQLparse()
- any rule calling sp_head::restore_lex()
- lex_end()
- x_free(lex->yacc_yyss), xfree(lex->yacc_yyvs)
The root cause is the implementation of stored procedures, which breaks the
assumption from 4.1 that there is only one LEX structure per parser call.
The solution is to separate the LEX structure into:
- attributes that represent a statement (the current LEX structure),
- attributes that relate to the syntax parser itself (Yacc_state),
so that parsing multiple statements in stored programs can create multiple
LEX structures while not changing the unique Yacc_state.
Now, Yacc_state and the existing Lex_input_stream are aggregated into
Parser_state, a structure that represent the complete state of the (Lexical +
Syntax) parser.
