Bug#41756 "Strange error messages about locks from InnoDB".
In JT_EQ_REF (join_read_key()) access method,
don't try to unlock rows in the handler, unless certain that
a) they were locked
b) they are not used.
Unlocking of rows is done by the logic of the nested join loop,
and is unaware of the possible caching that the access method may
have. This could lead to double unlocking, when a row
was unlocked first after reading into the cache, and then
when taken from cache, as well as to unlocking of rows which
were actually used (but taken from cache).
Delegate part of the unlocking logic to the access method,
and in JT_EQ_REF count how many times a record was actually
used in the join. Unlock it only if it's usage count is 0.
Implemented review comments.
mysql-test/r/innodb_lock_wait_timeout_1.result:
Update results (Bug41756).
mysql-test/t/innodb_lock_wait_timeout_1.test:
Add a test case (Bug#41756).
sql/item_subselect.cc:
Complete struct READ_RECORD initialization with a new
member to unlock records.
sql/records.cc:
Extend READ_RECORD API with a method to unlock read records.
sql/sql_select.cc:
In JT_EQ_REF (join_read_key()) access method,
don't try to unlock rows in the handler, unless certain that
a) they were locked
b) they are not used.
sql/sql_select.h:
Add members to TABLE_REF to count TABLE_REF buffer usage count.
sql/structs.h:
Update declarations.
with temporary tables
There were two problems the test case from this bug was
triggering:
1. JOIN::rollup_init() was supposed to wrap all constant Items
into another object for queries with the WITH ROLLUP modifier
to ensure they are never considered as constants and therefore
are written into temporary tables if the optimizer chooses to
employ them for DISTINCT/GROUP BY handling.
However, JOIN::rollup_init() was called before
make_join_statistics(), so Items corresponding to fields in
const tables could not be handled as intended, which was
causing all kinds of problems later in the query execution. In
particular, create_tmp_table() assumed all constant items
except "hidden" ones to be removed earlier by remove_const()
which led to improperly initialized Field objects for the
temporary table being created. This is what was causing crashes
and valgrind errors in storage engines.
2. Even when the above problem had been fixed, the query from
the test case produced incorrect results due to some
DISTINCT/GROUP BY optimizations being performed by the
optimizer that are inapplicable in the WITH ROLLUP case.
Fixed by disabling inapplicable DISTINCT/GROUP BY optimizations
when the WITH ROLLUP modifier is present, and splitting the
const-wrapping part of JOIN::rollup_init() into a separate
method which is now invoked after make_join_statistics() when
the const tables are already known.
mysql-test/r/olap.result:
Added a test case for bug #48131.
mysql-test/t/olap.test:
Added a test case for bug #48131.
sql/sql_select.cc:
1. Disabled inapplicable DISTINCT/GROUP BY optimizations when
the WITH ROLLUP modifier is present.
2. Split the const-wrapping part of JOIN::rollup_init() into a
separate method.
sql/sql_select.h:
Added rollup_process_const_fields() declaration.
subquery returning multiple rows
Error handling was missing when handling subqueires in WHERE
and when assigning a SELECT result to a @variable.
This caused crash(es).
Fixed by adding error handling code to both the WHERE
condition evaluation and to assignment to an @variable.
having clause...
The fix for bug 46184 was not very complete. It was not covering
views using temporary tables and multiple tables in a FROM clause.
Fixed by reverting the fix for 46184 and making a more general
check that is checking at the right execution stage and for all
of the non-supported cases.
Now PROCEDURE ANALYZE on non-top level SELECT is also forbidden.
Updated the analyse.test and subselect.test accordingly.
Queries with nested outer joins may lead to crashes or
bad results because an internal data structure is not handled
correctly.
The optimizer uses bitmaps of nested JOINs to determine
if certain table can be placed at a certain place in the
JOIN order.
It does maintain a bitmap describing in which JOINs
last placed table is nested.
When it puts a table it makes sure the bit of every JOIN that
contains the table in question is set (because JOINs can be nested).
It does that by recursively setting the bit for the next enclosing
JOIN when this is the first table in the JOIN and recursively
resetting the bit if it's the last table in the JOIN.
When it removes a table from the join order it should do the
opposite : recursively unset the bit if it's the only remaining
table in this join and and recursively set the bit if it's removing
the last table of a JOIN.
There was an error in how the bits was set for the upper levels :
when removing a table it was setting the bit for all the enclosing
nested JOINs even if there were more tables left in the current JOIN
(which practically means that the upper nested JOINs were not affected).
Fixed by stopping the recursion at the relevant level.
mysql-test/r/join.result:
Bug #42116: test case
mysql-test/t/join.test:
Bug #42116: test case
sql/sql_select.cc:
Bug #41116: don't go up and set the bits if more tables in
at the current JOIN level
line 138 when forcing a spatial index
Problem: "Spatial indexes can be involved in the search
for queries that use a function such as MBRContains()
or MBRWithin() in the WHERE clause".
Using spatial indexes for JOINs with =, <=> etc.
predicates is incorrect.
Fix: disable spatial indexes for such queries.
mysql-test/r/select.result:
Fix for bug#47019: Assertion failed: 0, file .\rt_mbr.c,
line 138 when forcing a spatial index
- test result.
mysql-test/t/select.test:
Fix for bug#47019: Assertion failed: 0, file .\rt_mbr.c,
line 138 when forcing a spatial index
- test case.
sql/sql_select.cc:
Fix for bug#47019: Assertion failed: 0, file .\rt_mbr.c,
line 138 when forcing a spatial index
- disable spatial indexes for queries which use
non-spatial conditions (e.g. NATURAL JOINs).
Temporary tables may set join->group to 0 even though there is
grouping. Also need to test if sum_func_count>0 when JOIN::exec()
decides whether to present results in a grouped manner.
sql/sql_select.cc:
Temporary tables may set join->group to 0 even though there is
grouping. Also need to test if sum_func_count>0 when JOIN::exec()
decides whether to present results in a grouped manner.
columns without where/group
Simple SELECT with implicit grouping used to return many rows if
the query was ordered by the aggregated column in the SELECT
list. This was incorrect because queries with implicit grouping
should only return a single record.
The problem was that when JOIN:exec() decided if execution needed
to handle grouping, it was assumed that sum_func_count==0 meant
that there were no aggregate functions in the query. This
assumption was not correct in JOIN::exec() because the aggregate
functions might have been optimized away during JOIN::optimize().
The reason why queries without ordering behaved correctly was
that sum_func_count is only recalculated if the optimizer chooses
to use temporary tables (which it does in the ordered case).
Hence, non-ordered queries were correctly treated as grouped.
The fix for this bug was to remove the assumption that
sum_func_count==0 means that there is no need for grouping. This
was done by introducing variable "bool implicit_grouping" in the
JOIN object.
mysql-test/r/func_group.result:
Add test for BUG#47280
mysql-test/t/func_group.test:
Add test for BUG#47280
sql/opt_sum.cc:
Improve comment for opt_sum_query()
sql/sql_class.h:
Add comment for variables in TMP_TABLE_PARAM
sql/sql_select.cc:
Introduce and use variable implicit_grouping instead of (!group_list && sum_func_count) in places that need to test if grouping is required. Also added comments for: optimization of aggregate fields for implicitly grouped queries (JOIN::optimize) and choice of end_select method (JOIN::execute)
sql/sql_select.h:
Add variable implicit_grouping, which will be TRUE for queries that contain aggregate functions but no GROUP BY clause. Also added comment to sort_and_group variable.
buffering is used
FORCE INDEX FOR ORDER BY now prevents the optimizer from
using join buffering. As a result the optimizer can use
indexed access on the first table and doesn't need to
sort the complete resultset at the end of the statement.
the fix is reverted from 5.1, mysql-pe as
unnecessary(no valgrind warnings there).
sql/sql_select.cc:
the fix is reverted from 5.1, mysql-pe as
unnecessary(no valgrind warnings there).
query
The fix for bug 46749 removed the check for OUTER_REF_TABLE_BIT
and substituted it for a check on the presence of
Item_ident::depended_from.
Removing it altogether was wrong : OUTER_REF_TABLE_BIT should
still be checked in addition to depended_from (because it's not
set in all cases and doesn't contradict to the check of depended_from).
Fixed by returning the old condition back as a compliment to the
new one.
The external 'for' loop in remove_dup_with_compare() handled
HA_ERR_RECORD_DELETED by just starting over without advancing
to the next record which caused an infinite loop.
This condition could be triggered on certain data by a SELECT
query containing DISTINCT, GROUP BY and HAVING clauses.
Fixed remove_dup_with_compare() so that we always advance to
the next record when receiving HA_ERR_RECORD_DELETED from
rnd_next().
mysql-test/r/distinct.result:
Added a test case for bug #46159.
mysql-test/t/distinct.test:
Added a test case for bug #46159.
sql/sql_select.cc:
Fixed remove_dup_with_compare() so that we always advance to
the next record when receiving HA_ERR_RECORD_DELETED from
rnd_next().
Memory allocated in TMP_TABLE_PARAM::copy_field is not cleaned up.
The fix is to clean up TMP_TABLE_PARAM::copy_field array in JOIN::destroy.
mysql-test/r/explain.result:
test result
mysql-test/t/explain.test:
test case
sql/sql_select.cc:
Memory allocated in TMP_TABLE_PARAM::copy_field is not cleaned up.
The fix is to clean up TMP_TABLE_PARAM::copy_field array in JOIN::destroy.
function,file sql_base.cc
When uncacheable queries are written to a temp table the optimizer must
preserve the original JOIN structure, because it is re-using the JOIN
structure to read from the resulting temporary table.
This was done only for uncacheable sub-queries.
But top level queries can also benefit from this mechanism, specially if
they're using index access and need a reset.
Fixed by not limiting the saving of JOIN structure to subqueries
exclusively.
Added a new test file to extend the existing (large) subquery.test.
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.
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.
mysql-test/r/type_newdecimal.result:
Add test case result for Bug#45261. Also, update test case to
reflect that an additive operation increases the precision of
the resulting type by 1.
mysql-test/t/type_newdecimal.test:
Add test case for Bug#45261
sql/field.cc:
Added DBUG_ASSERT to ensure object's invariant is maintained.
Implement method to create a field to hold a decimal value
from an item.
sql/field.h:
Explain member variable. Add method to create a new decimal field.
sql/item.cc:
The precision should only be capped when storing the value
on a table. Also, this makes it impossible to calculate the
integer part if Item::decimals (the scale) is larger than the
precision.
sql/item.h:
Simplify calculation of integer part.
sql/item_cmpfunc.cc:
Do not limit the precision. It will be capped later.
sql/item_func.cc:
Use new method for allocating a new decimal field.
Add a specialized method for retrieving the precision
of a user variable item.
sql/item_func.h:
Add method to return the precision of a user variable.
sql/item_sum.cc:
Use new method for allocating a new decimal field.
sql/my_decimal.h:
The integer part could be improperly calculated for a decimal
with 31 digits in the fractional part.
sql/sql_select.cc:
Use new method which truncates the integer or decimal parts
as needed.
In create_myisam_from_heap() mark all errors as fatal except
HA_ERR_RECORD_FILE_FULL for a HEAP table.
Not doing so could lead to problems, e.g. in a case when a
temporary MyISAM table gets overrun due to its MAX_ROWS limit
while executing INSERT/REPLACE IGNORE ... SELECT.
The SELECT execution was aborted, but the error was
converted to a warning due to IGNORE clause, so neither 'ok'
nor 'error' packet could be sent back to the client. This
condition led to hanging client when using 5.0 server, or
assertion failure in 5.1.
mysql-test/r/insert_select.result:
Added a test case for bug #46075.
mysql-test/t/insert_select.test:
Added a test case for bug #46075.
sql/sql_select.cc:
In create_myisam_from_heap() mark all errors as fatal except
HA_ERR_RECORD_FILE_FULL for a HEAP table.
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.
mysql-test/r/order_by.result:
Bug#46454: Test result.
mysql-test/t/order_by.test:
Bug#46454: Test case.
sql/sql_select.cc:
Bug#46454:
Problem 1 fixed in make_join_select()
Problem 2 fixed in test_if_skip_sort_order()
sql/table.h:
Bug#46454: Added comment to field.
use partial primary key if another index can prevent filesort
The fix for bug #28404 causes the covering ordering indexes to be
preferred unconditionally over non-covering and ref indexes.
Fixed by comparing the cost of using a covering index to the cost of
using a ref index even for covering ordering indexes.
Added an assertion to clarify the condition the local variables should
be in.
mysql-test/include/mix1.inc:
Bug #36259: fixed a non-stable test case
mysql-test/r/innodb_mysql.result:
Bug #36259 and #45828 : test case
mysql-test/t/innodb_mysql.test:
Bug #36259 and #45828 : test case
sql/sql_select.cc:
Bug #36259 and #45828 : don't consider covering indexes supperior to
ref keys.
Using DECIMAL constants with more than 65 digits in CREATE
TABLE ... SELECT led to bogus errors in release builds or
assertion failures in debug builds.
The problem was in inconsistency in how DECIMAL constants and
fields are handled internally. We allow arbitrarily long
DECIMAL constants, whereas DECIMAL(M,D) columns are limited to
M<=65 and D<=30. my_decimal_precision_to_length() was used in
both Item and Field code and truncated precision to
DECIMAL_MAX_PRECISION when calculating value length without
adjusting precision and decimals. As a result, a DECIMAL
constant with more than 65 digits ended up having length less
than precision or decimals which led to assertion failures.
Fixed by modifying my_decimal_precision_to_length() so that
precision is truncated to DECIMAL_MAX_PRECISION only for Field
object which is indicated by the new 'truncate' parameter.
Another inconsistency fixed by this patch is how DECIMAL
constants and expressions are handled for CREATE ... SELECT.
create_tmp_field_from_item() (which is used for constants) was
changed as a part of the bugfix for bug #24907 to handle long
DECIMAL constants gracefully. Item_func::tmp_table_field()
(which is used for expressions) on the other hand was still
using a simplistic approach when creating a Field_new_decimal
from a DECIMAL expression.
mysql-test/r/type_newdecimal.result:
Added a test case for bug #45262.
mysql-test/t/type_newdecimal.test:
Added a test case for bug #45262.
sql/item.cc:
Use the new 'truncate' parameter in
my_decimal_precision_to_length().
sql/item_cmpfunc.cc:
Use the new 'truncate' parameter in
my_decimal_precision_to_length().
sql/item_func.cc:
1. Use the new 'truncate' parameter in
my_decimal_precision_to_length().
2. Do not truncate decimal precision to DECIMAL_MAX_PRECISION
for additive expressions involving long DECIMAL constants.
3. Fixed an incosistency in how DECIMAL constants and
expressions are handled for CREATE ... SELECT.
sql/item_func.h:
Use the new 'truncate' parameter in
my_decimal_precision_to_length().
sql/item_sum.cc:
Use the new 'truncate' parameter in
my_decimal_precision_to_length().
sql/my_decimal.h:
Do not truncate precision to DECIMAL_MAX_PRECISION
when calculating length in
my_decimal_precision_to_length() if 'truncate' parameter
is FALSE.
sql/sql_select.cc:
1. Use the new 'truncate' parameter in
my_decimal_precision_to_length().
2. Use a more correct logic when adjusting value's length.
The TABLE::reginfo.impossible_range is used by the optimizer to indicate
that the condition applied to the table is impossible. It wasn't initialized
at table opening and this might lead to an empty result on complex queries:
a query might set the impossible_range flag on a table and when the query finishes,
all tables are returned back to the table cache. The next query that uses the table
with the impossible_range flag set and an index over the table will see the flag
and thus return an empty result.
The open_table function now initializes the TABLE::reginfo.impossible_range
variable.
mysql-test/r/select.result:
A test case for the bug#45266: Uninitialized variable lead to an empty result.
mysql-test/t/select.test:
A test case for the bug#45266: Uninitialized variable lead to an empty result.
sql/sql_base.cc:
Bug#45266: Uninitialized variable lead to an empty result.
The open_table function now initializes the TABLE::reginfo.impossible_range
variable.
sql/sql_select.cc:
Bug#45266: Uninitialized variable lead to an empty result.
The open_table function now initializes the TABLE::reginfo.impossible_range
variable.
sql/structs.h:
Bug#45266: Uninitialized variable lead to an empty result.
A comment is added.
with gcc 4.3.2
Compiling MySQL with gcc 4.3.2 and later produces a number of
warnings, many of which are new with the recent compiler
versions.
This bug will be resolved in more than one patch to limit the
size of changesets. This is the second patch, fixing more
of the warnings.
crashes server!
The problem affects the scenario when index merge is followed by a filesort
and the sort buffer is not big enough for all the sort keys.
In this case the filesort function will read the data to the end through the
index merge quick access method (and thus closing the cursor etc),
but will leave the pointer to the quick select method in place.
It will then create a temporary file to hold the results of the filesort and
will add it as a sort output file (in sort.io_cache).
Note that filesort will copy the original 'sort' structure in an automatic
variable and restore it after it's done.
As a result at exiting filesort() we have a sort.io_cache filled in and
nothing else (as a result of close of the cursors at end of reading data
through index merge).
Now create_sort_index() will note that there is a select and will clean it up
(as it's been used already by filesort() reading the data in). While doing that
a special case in the index merge destructor will clean up the sort.io_cache,
assuming it's an output of the index merge method and is not needed anymore.
As a result the code that tries to read the data back from the filesort output
will get no data in both memory and disk and will crash.
Fixed similarly to how filesort() does it : by copying the sort.io_cache structure
to a local variable, removing the pointer to the io_cache (so that it's not freed
by QUICK_INDEX_MERGE_SELECT::~QUICK_INDEX_MERGE_SELECT) and restoring the original
structure (together with the valid pointer) after the cleanup is done.
This is a safe thing to do because all the structures are already cleaned up by
hitting the end of the index merge's read method (QUICK_INDEX_MERGE_SELECT::get_next())
and the cleanup code being written in a way that tolerates repeating cleanups.
mysql-test/r/index_merge.result:
Bug #44810: test case
mysql-test/t/index_merge.test:
Bug #44810: test case
sql/sql_select.cc:
Bug #44810: preserve the io_cache produced by filesort while cleaning up
the index merge quick access method (QUICK_INDEX_MERGE_SELECT).
with gcc 4.3.2
Compiling MySQL with gcc 4.3.2 and later produces a number of
warnings, many of which are new with the recent compiler
versions.
This bug will be resolved in more than one patch to limit the
size of changesets. This is the second patch, fixing more
of the warnings.
uninitialized variable used as subscript
Grouping select from a "constant" InnoDB table (a table
of a single row) joined with other tables caused a crash.
mysql-test/r/innodb_mysql.result:
Added test case for bug bug #44886.
mysql-test/t/innodb_mysql.test:
Added test case for bug bug #44886.
sql/sql_select.cc:
Bug #44886: SIGSEGV in test_if_skip_sort_order() -
uninitialized variable used as subscript
1. The test_if_order_by_key function returned unitialized
used_key_parts parameter in case of a "constant" InnoDB
table. Calling function uses this parameter values as
an array index, thus sometimes it caused a crash.
The test_if_order_by_key function has been modified
to set used_key_parts to 0 (no need for ordering).
2. The test_if_skip_sort_order function has been
modified to accept zero used_key_parts value and
to prevent an array access by negative index.
Holding on to the temporary inno hash index latch is an optimization in
many cases, but a pessimization in some others.
Release temporary latches for those corner cases we (or rather, or customers,
thanks!) have identified, that is, when we are about to do something that
might take a really long time, like REPAIR or filesort.
sql/ha_myisam.cc:
Let go of (inno, for now) latch when doing MyISAM-repair.
(optimize passes through repair.) ("Stuck" in "Repair with
keycache".)
sql/sql_insert.cc:
Let go of (inno, for now) latch when doing CREATE...SELECT
in select_insert::send_data() -- it might take a while.
("stuck" in "Sending data")
sql/sql_select.cc:
Release temporary (inno, for now) latch on
- free_tmp_table() (this can take surprisingly long, "removing tmp table")
- create_myisam_from_heap() (HEAP table overflowing onto disk as MyISAM,
"converting HEAP to MyISAM")
HAVING
When calculating GROUP BY the server caches some expressions. It does
that by allocating a string slot (Item_copy_string) and assigning the
value of the expression to it. This effectively means that the result
type of the expression can be changed from whatever it was to a string.
As this substitution takes place after the compile-time result type
calculation for IN but before the run-time type calculations,
it causes the type calculations in the IN function done at run time
to get unexpected results different from what was prepared at compile time.
In the CASE ... WHEN ... THEN ... statement there was a similar problem
and it was solved by artificially adding a STRING argument to the set of
types of the IN/CASE arguments at compile time, so if any of the
arguments of the CASE function changes its type to a string it will
still be covered by the information prepared at compile time.
mysql-test/include/mix1.inc:
Bug #44399: extended the test to cover the different types
mysql-test/r/func_in.result:
Bug #44399: test case
mysql-test/r/innodb_mysql.result:
Bug #44399: extended the test to cover the different types
mysql-test/t/func_in.test:
Bug #44399: test case
sql/item.cc:
Bug #44399: Implement typed caching for GROUP BY
sql/item.h:
Bug #44399: Implement typed caching for GROUP BY
sql/item_cmpfunc.cc:
Bug #44399: remove the special case
sql/sql_select.cc:
Bug #44399: Implement typed caching for GROUP BY
SQL_SELECT::test_quick_select
The crash was caused by an incomplete cleanup of JOIN_TAB::select
during the filesort of rows for GROUP BY clause inside a subquery.
Queries where a quick index access is replaced with filesort was
was affected. For example:
SELECT 1 FROM
(SELECT COUNT(DISTINCT c1) FROM t1
WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x
Quick index access related data in the SQL_SELECT::test_quick_select
function was inconsistent after an incomplete cleanup.
This function has been completed to prevent crashes in the
SQL_SELECT::test_quick_select function.
mysql-test/include/mix1.inc:
Add test case for bug #44290.
mysql-test/r/innodb_mysql.result:
Add test case for bug #44290.
sql/sql_select.cc:
Bug #44290: explain crashes for subquery with distinct in
SQL_SELECT::test_quick_select
Quick index access related data in the SQL_SELECT::test_quick_select
function was inconsistent after an incomplete cleanup.
This function has been completed to prevent crashes in the
SQL_SELECT::test_quick_select function.
'INSERT ... SELECT' statements
The code that produces result rows expected that a duplicate row
error could not occur in INSERT ... SELECT statements with
unfulfilled WHERE conditions. This may happen, however, if the
SELECT list contains only aggregate functions.
Fixed by checking if an error occured before trying to send EOF
to the client.
mysql-test/r/insert_select.result:
Bug#44306: Test result
mysql-test/t/insert_select.test:
Bug#44306: Test case
sql/sql_select.cc:
Bug#44306: Fix
EXPLAIN EXTENDED of nested query containing a error:
1054 Unknown column '...' in 'field list'
may cause a server crash.
Parse error like described above forces a call to
JOIN::destroy() on malformed subquery.
That JOIN::destroy function closes and frees temporary
tables. However, temporary fields of these tables
may be listed in st_select_lex::group_list of outer
query, and that st_select_lex may not cleanup them
properly. So, after the JOIN::destroy call that
st_select_lex::group_list may have Item_field
objects with dangling pointers to freed temporary
table Field objects. That caused a crash.
mysql-test/r/subselect3.result:
Added test case for bug #37362.
mysql-test/t/subselect3.test:
Added test case for bug #37362.
sql/sql_select.cc:
Bug #37362: Crash in do_field_eq
The JOIN::destroy function has been modified to
cleanup temporary table column items.
Original commentary:
Bug #37348: Crash in or immediately after JOIN::make_sum_func_list
The optimizer pulls up aggregate functions which should be aggregated in
an outer select. At some point it may substitute such a function for a field
in the temporary table. The setup_copy_fields function doesn't take this
into account and may overrun the copy_field buffer.
Fixed by filtering out the fields referenced through the specialized
reference for aggregates (Item_aggregate_ref).
Added an assertion to make sure bugs that cause similar discrepancy
don't go undetected.
mysql-test/r/func_group.result:
Backport bug #37348 fix 5.1 --> 5.0.
mysql-test/t/func_group.test:
Backport bug #37348 fix 5.1 --> 5.0.
sql/item.cc:
Backport bug #37348 fix 5.1 --> 5.0.
sql/item.h:
Backport bug #37348 fix 5.1 --> 5.0.
sql/sql_select.cc:
Backport bug #37348 fix 5.1 --> 5.0.
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.
mysql-test/r/select.result:
Fix for bug #42957: no results from
select where .. (col=col and col=col) or ... (false expression)
- test result.
mysql-test/t/select.test:
Fix for bug #42957: no results from
select where .. (col=col and col=col) or ... (false expression)
- test case.
sql/sql_select.cc:
Fix for bug #42957: no results from
select where .. (col=col and col=col) or ... (false expression)
- replacing equality predicates by multiple equality items check
if we eliminate all the predicates at the AND level and
replace them with TRUE if so.
mysqld is optimized for the default
case (up to 64-indices); for a greater
number of indices it goes through a
different code path. As that code-path
is a compile-time option and can not
easily be covered in standard tests,
bitrot occurred. key-fields need an
explicit initialization in the non-
optimized case; this setup was
presumably not added when a new key-
vector was added.
Changeset adds the necessary
initialisations.
No test case added due to dependence
on compile-time option.
sql/sql_select.cc:
Init merge_keys as well. If we don't,
things blow up badly outside of the
optimized-for-64-keys case!
sql/table.cc:
Init merge_keys as well. If we don't,
things blow up badly outside of the
optimized-for-64-keys case!
connections
The problem is that tables can enter open table cache for a thread without
being properly cleaned up. This can happen if make_join_statistics() fails
to read a const table because of e.g. a deadlock. It does set a member of
TABLE structure to a value it allocates, but doesn't clean-up this setting
on error nor does it set the rest of the members in JOIN to allow for
automatic cleanup.
As a result when such an error occurs and the next statement depends re-uses
the table from the open tables cache it will get it with this
TABLE::reginfo.join_tab pointing to a memory area that's freed.
Fixed by making sure make_join_statistics() cleans up TABLE::reginfo.join_tab
on error.
mysql-test/r/innodb_mysql.result:
Bug #42419: test case
mysql-test/t/innodb_mysql-master.opt:
Bug #42419: increase the timeout so it covers te conservative
sleep 3 in the test
mysql-test/t/innodb_mysql.test:
Bug #42419: test case
sql/sql_select.cc:
Bug #42419: clean up the members of TABLE on failure in
make_join_statisitcs()
- Remove bothersome warning messages. This change focuses on the warnings
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length
ORDER BY could cause a server crash
Dependent subqueries like
SELECT COUNT(*) FROM t1, t2 WHERE t2.b
IN (SELECT DISTINCT t2.b FROM t2 WHERE t2.b = t1.a)
caused a memory leak proportional to the
number of outer rows.
The make_simple_join() function has been modified to
JOIN class method to store join_tab_reexec and
table_reexec values in the parent join only
(make_simple_join of tmp_join may access these values
via 'this' pointer of the parent JOIN).
NOTE: this patch doesn't include standard test case (this is
"out of memory" bug). See bug #42037 page for test cases.
sql/sql_select.cc:
Bug #42037: Queries containing a subquery with DISTINCT and
ORDER BY could cause a server crash
The make_simple_join() function has been modified to
JOIN class method to store join_tab_reexec and
table_reexec values in the parent join only.
sql/sql_select.h:
Bug #42037: Queries containing a subquery with DISTINCT and
ORDER BY could cause a server crash
1. The make_simple_join() function has been modified to
JOIN class method.
2. Type of JOIN::table_reexec field has been changed from
TABLE** to TABLE *table_reexec[1]: this field always was
NULL or a pointer to one-element array of pointers, so
a pointer to a pointer has been replaced with one pointer
and unnecessary memory allocation has been eliminated.
messed up
"ROW(...) IN (SELECT ... FROM DUAL)" always returned TRUE.
Item_in_subselect::row_value_transformer rewrites "ROW(...)
IN SELECT" conditions into the "EXISTS (SELECT ... HAVING ...)"
form.
For a subquery from the DUAL pseudotable resulting HAVING
condition is an expression on constant values, so further
transformation with optimize_cond() eliminates this HAVING
condition and resets JOIN::having to NULL.
Then JOIN::exec treated that NULL as an always-true-HAVING
and that caused a bug.
To distinguish an optimized out "HAVING TRUE" clause from
"HAVING FALSE" we already have the JOIN::having_value flag.
However, JOIN::exec() ignored JOIN::having_value as described
above as if it always set to COND_TRUE.
The JOIN::exec method has been modified to take into account
the value of the JOIN::having_value field.
mysql-test/r/subselect3.result:
Added test case for bug #39069.
mysql-test/t/subselect3.test:
Added test case for bug #39069.
sql/sql_select.cc:
Bug #39069: <row constructor> IN <table-subquery> seriously
messed up
The JOIN::exec method has been modified to take into account
the value of the JOIN::having_value field.
The greedy optimizer tracks the current level of nested joins and the position
inside these by setting and maintaining a state that's global for the whole FROM
clause.
This state was correctly maintained inside the selection of the next partial plan
table (in best_extension_by_limited_search()).
greedy_search() also moves the current position by adding the last partial match
table when there's not enough tables in the partial plan found by
best_extension_by_limited_search().
This may require update of the global state variables that describe the current
position in the plan if the last table placed by greedy_search is not a top-level
join table.
Fixed by updating the state after placing the partial plan table in greedy_search()
in the same way this is done on entering the best_extension_by_limited_search().
Fixed the signature of the function called to update the state :
check_interleaving_with_nj
mysql-test/r/greedy_optimizer.result:
Bug #38795: test case
mysql-test/t/greedy_optimizer.test:
Bug #38795: test case
sql/sql_select.cc:
Bug #38795: correctly update current position when placing
the next partial plan table in greedy_search().
Table could be marked dependent because it is
either 1) an inner table of an outer join, or 2) it is a part of
STRAIGHT_JOIN. In case of STRAIGHT_JOIN table->maybe_null should not
be assigned. The fix is to set st_table::maybe_null to 'true' only
for those tables which are used in outer join.
mysql-test/r/select.result:
test result
mysql-test/t/select.test:
test case
sql/sql_select.cc:
Table could be marked dependent because it is
either 1) an inner table of an outer join, or 2) it is a part of
STRAIGHT_JOIN. In case of STRAIGHT_JOIN table->maybe_null should not
be assigned. The fix is to set st_table::maybe_null to 'true' only
for those tables which are used in outer join.
sql/sql_select.h:
added comment
Bug#37671 crash on prepared statement + cursor + geometry + too many open files!
if mysql_execute_command() returns error then free materialized_cursor object.
is_rnd_inited is added to satisfy rnd_end() assertion
(handler may be uninitialized in some cases)
sql/sql_cursor.cc:
if mysql_execute_command() returns error then free materialized_cursor object.
is_rnd_inited is added to satisfy rnd_end() assertion
(handler may be uninitialized in some cases)
sql/sql_select.cc:
added result check
tests/mysql_client_test.c:
test case
if table has bit fields then uneven bits(if exist) are stored into null bits place.
So we need to copy null bits in case of uneven bit field presence.
mysql-test/r/type_bit.result:
test result
mysql-test/t/type_bit.test:
test case
sql/sql_select.cc:
if table has bit fields then uneven bits(if exist) are stored into null bits place.
So we need to copy null bits in case of uneven bit field presence.
ONLY_FULL_GROUP_BY
The check for non-aggregated columns in queries with aggregate function, but without
GROUP BY was treating all the parts of the query as if they are in the SELECT list.
Fixed by ignoring the non-aggregated fields in the WHERE clause.
mysql-test/r/func_group.result:
Bug #39656: test case
mysql-test/t/func_group.test:
Bug #39656: test case
sql/sql_select.cc:
Bug #39656: ignore the new non-aggregated column refs in a WHERE
by saving the state so far and then adding only the new values of the other
parts of the bitmask.
fails after the first time
Two separate problems :
1. When flattening joins the linked list used for name resolution
(next_name_resolution_table) was not updated.
Fixed by updating the pointers when extending the table list
2. The items created by expanding a * (star) as a column reference
were marked as fixed, but no cached table was assigned to them
(unlike what Item_field::fix_fields does).
Fixed by assigning a cached table (so the re-preparation is done
faster).
Note that the fix for #2 hides the fix for #1 in most cases
(except when a table reference cannot be cached).
mysql-test/r/sp.result:
Bug #33811: test case
mysql-test/t/sp.test:
Bug #33811: test case
sql/sql_base.cc:
Bug #33811: cache the table for Item_fields created by expanding '*'
sql/sql_select.cc:
Bug #33811: maintain a correct name resolution chain when
flattening joins.
Server crashed during a sort order optimization
of a dependent subquery:
SELECT
(SELECT t1.a FROM t1, t2
WHERE t1.a = t2.b AND t2.a = t3.c
ORDER BY t1.a)
FROM t3;
Bitmap of tables, that the reference to outer table
column uses, in addition to the regular table bit
has the OUTER_REF_TABLE_BIT bit set.
The only_eq_ref_tables function traverses this map
bit by bit simultaneously with join->map2table list.
Obviously join->map2table never contains an entry
for the OUTER_REF_TABLE_BIT pseudo-table, so the
server crashed there.
The only_eq_ref_tables function has been modified
to traverse regular table bits only like the
update_depend_map function (resetting of the
OUTER_REF_TABLE_BIT there is enough, but
resetting of the whole set of PSEUDO_TABLE_BITS
is used there for sure).
mysql-test/r/order_by.result:
Added test case for bug #39844.
mysql-test/t/order_by.test:
Added test case for bug #39844.
sql/sql_select.cc:
Bug #39844: Query Crash Mysql Server 5.0.67
The only_eq_ref_tables function has been modified
to traverse regular table bits only like the
update_depend_map function (resetting of the
OUTER_REF_TABLE_BIT there is enough, but
resetting of the whole set of PSEUDO_TABLE_BITS
is used there for sure).