field references
This error requires a combination of factors :
1. An "impossible where" in the outermost SELECT
2. An aggregate in the outermost SELECT
3. A correlated subquery with a WHERE clause that includes an outer
field reference as a top level WHERE sargable predicate
When JOIN::optimize detects an "impossible WHERE" it will bail out
without doing the rest of the work and initializations. It will not
call make_join_statistics() as well. And make_join_statistics fills
in various structures for each table referenced.
When processing the result of the "impossible WHERE" the query must
send a single row of data if there are aggregate functions in it.
In this case the server marks all the aggregates as having received
no rows and calls the relevant Item::val_xxx() method on the SELECT
list. However if this SELECT list happens to contain a correlated
subquery this subquery is evaluated in a normal evaluation mode.
And if this correlated subquery has a reference to a field from the
outermost "impossible where" SELECT the add_key_fields will mistakenly
consider the outer field reference as a "local" field reference when
looking for sargable predicates.
But since the SELECT where the outer field reference refers to is not
completely initialized due to the "impossible WHERE" in this level
we'll get a NULL pointer reference.
Fixed by making a better condition for discovering if a field is "local"
to the SELECT level being processed.
It's not enough to look for OUTER_REF_TABLE_BIT in this case since
for outer references to constant tables the Item_field::used_tables()
will return 0 regardless of whether the field reference is from the
local SELECT or not.
When a connection is dropped any remaining temporary table is also automatically
dropped and the SQL statement of this operation is written to the binary log in
order to drop such tables on the slave and keep the slave in sync. Specifically,
the current code base creates the following type of statement:
DROP /*!40005 TEMPORARY */ TABLE IF EXISTS `db`.`table`;
Unfortunately, appending the database to the table name in this manner circumvents
the replicate-rewrite-db option (and any options that check the current database).
To solve the issue, we started writing the statement to the binary as follows:
use `db`; DROP /*!40005 TEMPORARY */ TABLE IF EXISTS `table`;
The crash happens because select_union object is used as result set
for queries which have derived tables.
select_union use temporary table as data storage and if
fields count exceeds 10(count of values for procedure ANALYSE())
then we get a crash on fill_record() function.
Problem was that the partition containing NULL values
was pruned away, since '2001-01-01' < '2001-02-00' but
TO_DAYS('2001-02-00') is NULL.
Added the NULL partition for RANGE/LIST partitioning on TO_DAYS()
function to be scanned too.
Also fixed a bug that added ALLOW_INVALID_DATES to sql_mode
(SELECT * FROM t WHERE date_col < '1999-99-99' on a RANGE/LIST
partitioned table would add it).
There were a problem since pruning uses the field
for comparison (while evaluate_join_record uses longlong),
resulting in pruning failures when comparing DATE to DATETIME.
Fix was to always comparing DATE vs DATETIME as DATETIME,
by adding ' 00:00:00' to the DATE string.
And adding optimization for comparing with 23:59:59, so that
DATETIME_col > '2001-02-03 23:59:59' ->
TO_DAYS(DATETIME_col) > TO_DAYS('2001-02-03 23:59:59') instead
of '>='.
The problem was that creating a DECIMAL column from a decimal
value could lead to a failed assertion as decimal values can
have a higher precision than those attached to a table. The
assert could be triggered by creating a table from a decimal
with a large (> 30) scale. Also, there was a problem in
calculating the number of digits in the integral and fractional
parts if both exceeded the maximum number of digits permitted
by the new decimal type.
The solution is to ensure that truncation procedure is executed
when deducing a DECIMAL column from a decimal value of higher
precision. If the integer part is equal to or bigger than the
maximum precision for the DECIMAL type (65), the integer part
is truncated to fit and the fractional becomes zero. Otherwise,
the fractional part is truncated to fit into the space left
after the integer part is copied.
This patch borrows code and ideas from Martin Hansson's patch.
INSERT ... SELECT ...
Problem was that when bulk insert is used on an empty
table/partition, it disables the indexes for better
performance, but in this specific case it also tries
to read from that partition using an index, which is
not possible since it has been disabled.
Solution was to allow index reads on disabled indexes
if there are no records.
Also reverted the patch for bug#38005, since that was a workaround
in the partitioning engine instead of a fix in myisam.
(temporary) TABLE, crash
Problem: if one has an open "HANDLER t1", further "TRUNCATE t1"
doesn't close the handler and leaves handler table hash in an
inconsistent state, that may lead to a server crash.
Fix: TRUNCATE should implicitly close all open handlers.
Doc. request: the fact should be described in the manual accordingly.
view that has Group By
Table access rights checking function check_grant() assumed
that no view is opened when it's called.
This is not true with nested views where the inner view
needs materialization. In this case the view is already
materialized when check_grant() is called for it.
This caused check_grant() to not look for table level
grants on the materialized view table.
Fixed by checking if a view is already materialized and if
it is check table level grants using the original table name
(not the ones of the materialized temp table).
on SHOW CREATE TRIGGER + MERGE table
Problem: SHOW CREATE TRIGGER erroneously relies on fact
that we have the only underlying table for a trigger
(wrong for merge tables).
Fix: remove erroneous assert().
Replication SQL thread does not set database default charset to
thd->variables.collation_database properly, when executing LOAD DATA binlog.
This bug can be repeated by using "LOAD DATA" command in STATEMENT mode.
This patch adds code to find the default character set of the current database
then assign it to thd->db_charset when slave server begins to execute a relay log.
The test of this bug is added into rpl_loaddata_charset.test
The test for the 45806 entry in our bug DB got applied twice,
in different places for the "view.test" and "view.result" files.
The fix is to simply remove the erroneous insertion.
All committed result differences have either been verified by me or copied from Oracle's provided
results (storage/innodb_plugin/mysql-test/*.result, storage/innodb_plugin/mysql-test/patches).
Problem 1:
When the 'Using index' optimization is used, the optimizer may still - after
cost-based optimization - decide to use another index in order to avoid using
a temporary table. But when this happens, the flag to the storage engine to
read index only (not table) was still set. Fixed by resetting the flag in the
storage engine and TABLE structure in the above scenario, unless the new index
allows for the same optimization.
Problem 2:
When a 'ref' access method was employed by cost-based optimizer, (when the column
is non-NULLable), it was assumed that it needed no initialization if 'quick' access
methods (since they are based on range scan). When ORDER BY optimization overrides
the decision, however, it expects to have this initialized and hence crashes.
Fixed in 5.1 (was fixed in 6.0 already) by initializing 'quick' even when there's
'ref' access.
when partition is reoganized.
Problem was that table->timestamp_field_type was not changed
before copying rows between partitions.
fixed by setting it to TIMESTAMP_NO_AUTO_SET as the first thing
in fast_alter_partition_table, so that all if-branches is covered.
column on partitioned table
An assertion 'ASSERT_COULUMN_MARKED_FOR_READ' is failed if the query
is executed with index containing double column on partitioned table.
The problem is that assertion expects all the fields which are read,
to be in the read_set.
In this query only the field 'a' is in the readset as the tables in
the query are joined by the field 'a' and so the assertion fails
expecting other field 'b'.
Since the function cmp() is just comparison of two parameters passed,
the assertion is not required.
Fixed by removing the assertion in the double fields comparision
function and also fixed the index initialization to do ordered
index scan with RW LOCK which ensures all the fields from a key are in
the read_set.
Note: this bug is not reproducible with other datatypes because the
assertion doesn't exist in comparision function for other
datatypes.
bzr branch mysql-5.1-performance-version mysql-trunk # Summit
cd mysql-trunk
bzr merge mysql-5.1-innodb_plugin # which is 5.1 + Innodb plugin
bzr rm innobase # remove the builtin
Next step: build, test fixes.
Install procedure does not copy *.inc files located under the mysql-test/t directory.
Therefore, this patch moves the rpl_trigger.inc to the mysql-test/include directory.
The test case fails sporadically on Windows while trying to overwrite an unused
binary log. The problem stems from the fact that MySQL on Windows does not
immediately unlock/release a file while the process that opened and closed it is
still running. In BUG 38603, this issue was circumvented by stopping the MySQL
process, copying the file and then restarting the MySQL process.
Unfortunately, such facilities are not available in the 5.0. Other approaches
such as stopping the slave and issuing change master do not work because the relay
log file and index are not closed when a slave is stopped. So to fix the problem,
we simply don't run on windows the part of the test that was failing.
when used with --tab
1) New syntax: added CHARACTER SET clause to the
SELECT ... INTO OUTFILE (to complement the same clause in
LOAD DATA INFILE).
mysqldump is updated to use this in --tab mode.
2) ESCAPED BY/ENCLOSED BY field parameters are documented as
accepting CHAR argument, however SELECT .. INTO OUTFILE
silently ignored rests of multisymbol arguments.
For the symmetrical behavior with LOAD DATA INFILE the
server has been modified to fail with the same error:
ERROR 42000: Field separator argument is not what is
expected; check the manual
3) Current LOAD DATA INFILE recognizes field/line separators
"as is" without converting from client charset to data
file charset. So, it is supposed, that input file of
LOAD DATA INFILE consists of data in one charset and
separators in other charset. For the compatibility with
that [buggy] behaviour SELECT INTO OUTFILE implementation
has been saved "as is" too, but the new warning message
has been added:
Non-ASCII separator arguments are not fully supported
This message warns on field/line separators that contain
non-ASCII symbols.
