FROM A FUNCTION
Scenario:
In a stored procedure, CREATE TABLE statement is not allowed. But an
exception is provided for CREATE TEMPORARY TABLE. We can create a temporary
table in a stored procedure.
Let there be two stored functions f1 and f2 and two stored procedures p1 and
p2. Their properties are as follows:
. stored function f1() calls stored procedure p1().
. stored function f2() calls stored procedure p2().
. stored procedure p1() creates temporary table t1.
. stored procedure p2() does DML on t1.
Consider the following situation:
1. Autocommit mode is on.
2. select f1()
3. select f2()
Step 2: In this step, t1 would be created via p1(). A table level transaction
lock would have been taken. The ::external_lock() would not have been called
on this table. At the end of step 2, because of autocommit mode on, this table
level lock will be released.
Step 3: When we execute DML on table t1 via p2() we have two problems:
Problem 1:
The function ha_innobase::external_lock() would have been called but since
it is a select query no table level locks would have been taken. Hence the
following assert will fail:
ut_ad(lock_table_has(thr_get_trx(thr), index->table, LOCK_IX));
Solution:
The solution would be to identify this situation and take a table level lock
and use the proper lock type prebuilt->select_lock_type = LOCK_X for DML
operations.
Problem 2:
Another problem is that in step 3, ha_innobase::open() is never called on
the table t1.
Solution:
The solution would be to identify this situation and call re-init the handler
of table t1.
rb#6429 approved by Krunal.
FROM A FUNCTION
Scenario:
In a stored procedure, CREATE TABLE statement is not allowed. But an
exception is provided for CREATE TEMPORARY TABLE. We can create a temporary
table in a stored procedure.
Let there be two stored functions f1 and f2 and two stored procedures p1 and
p2. Their properties are as follows:
. stored function f1() calls stored procedure p1().
. stored function f2() calls stored procedure p2().
. stored procedure p1() creates temporary table t1.
. stored procedure p2() does DML on t1.
Consider the following situation:
1. Autocommit mode is on.
2. select f1()
3. select f2()
Step 2: In this step, t1 would be created via p1(). A table level transaction
lock would have been taken. The ::external_lock() would not have been called
on this table. At the end of step 2, because of autocommit mode on, this table
level lock will be released.
Step 3: When we execute DML on table t1 via p2() we have two problems:
Problem 1:
The function ha_innobase::external_lock() would have been called but since
it is a select query no table level locks would have been taken. Hence the
following assert will fail:
ut_ad(lock_table_has(thr_get_trx(thr), index->table, LOCK_IX));
Solution:
The solution would be to identify this situation and take a table level lock
and use the proper lock type prebuilt->select_lock_type = LOCK_X for DML
operations.
Problem 2:
Another problem is that in step 3, ha_innobase::open() is never called on
the table t1.
Solution:
The solution would be to identify this situation and call re-init the handler
of table t1.
rb#6429 approved by Krunal.
Merged lp:maria/maria-10.0-galera up to revision 3880.
Added a new functions to handler API to forcefully abort_transaction,
producing fake_trx_id, get_checkpoint and set_checkpoint for XA. These
were added for future possiblity to add more storage engines that
could use galera replication.
Merged lp:maria/maria-10.0-galera up to revision 3879.
Added a new functions to handler API to forcefully abort_transaction,
producing fake_trx_id, get_checkpoint and set_checkpoint for XA. These
were added for future possiblity to add more storage engines that
could use galera replication.
Analysis: InnoDB writes also files that do not contain FIL-header.
This could lead incorrect analysis on os_fil_read_func function
when it tries to see is page page compressed based on FIL_PAGE_TYPE
field on FIL-header. With bad luck uncompressed page that does
not contain FIL-headed, the byte on FIL_PAGE_TYPE position could
indicate that page is page comrpessed.
Fix: Upper layer must indicate is file space page compressed
or not. If this is not yet known, we need to read the FIL-header
and find it out. Files that we know that are not page compressed
we can always just provide FALSE.
Problem:
When a unique secondary index is scanned for duplicate checking, gap locks
were not taken if the transaction had isolation level <= READ COMMITTED.
This change was done while fixing Bug #16133801 UNEXPLAINABLE INNODB UNIQUE
INDEX LOCKS ON DELETE + INSERT WITH SAME VALUES (rb#2035). Because of this
the duplicate check logic failed, and resulted in duplicate values in unique
secondary index.
Solution:
When a unique secondary index is scanned for duplicate checking, gap locks
must be taken irrespective of the transaction isolation level. This is
achieved by reverting rb#2035.
rb#5910 approved by Jimmy
Problem:
When a unique secondary index is scanned for duplicate checking, gap locks
were not taken if the transaction had isolation level <= READ COMMITTED.
This change was done while fixing Bug #16133801 UNEXPLAINABLE INNODB UNIQUE
INDEX LOCKS ON DELETE + INSERT WITH SAME VALUES (rb#2035). Because of this
the duplicate check logic failed, and resulted in duplicate values in unique
secondary index.
Solution:
When a unique secondary index is scanned for duplicate checking, gap locks
must be taken irrespective of the transaction isolation level. This is
achieved by reverting rb#2035.
rb#5910 approved by Jimmy
This patch allows up to 64K pages for tables with DYNAMIC, COMPACT
and REDUNDANT row types. Tables with COMPRESSED row type allows
still only <= 16K page size. Note that single row size must be
still <= 16K and max key length is not affected.
THE PERFORMANCE UNDER HEAVY INSERT
Problem:
There are three memset call to allocate memory for system fields
in each insert.
Solution:
Instead of calling it in 3 times, we can combine it into
one memset call. It will reduce the CPU usage under heavy insert.
Approved by Marko rb-4916
THE PERFORMANCE UNDER HEAVY INSERT
Problem:
There are three memset call to allocate memory for system fields
in each insert.
Solution:
Instead of calling it in 3 times, we can combine it into
one memset call. It will reduce the CPU usage under heavy insert.
Approved by Marko rb-4916
Problem:
In the clustered index, when an update operation is done the overall
scenario (after rb#4479) is as follows:
1. Delete mark the old record that is to be updated.
2. The old record disowns the blobs.
3. Insert the new record into clustered index.
4. For non-updated blobs, new record must own it. Verified by assert.
5. For non-updated blobs, in new record marked as inherited.
Scenario involving DB_LOCK_WAIT:
If step 3 times out, then we will skip 1 and 2 and will continue from
step 3. This skipping is achieved by the UPD_NODE_INSERT_BLOB state.
In this case, step 4 is not correct. Because of step 1, the new
record need not own the blobs. Hence the assert failure.
Solution:
The assert in step 4 is removed. Instead code is added to ensure that
the record owns the blob.
Note:
This is a regression caused by rb#4479.
rb#4571 approved by Marko
Problem:
In the clustered index, when an update operation is done the overall
scenario (after rb#4479) is as follows:
1. Delete mark the old record that is to be updated.
2. The old record disowns the blobs.
3. Insert the new record into clustered index.
4. For non-updated blobs, new record must own it. Verified by assert.
5. For non-updated blobs, in new record marked as inherited.
Scenario involving DB_LOCK_WAIT:
If step 3 times out, then we will skip 1 and 2 and will continue from
step 3. This skipping is achieved by the UPD_NODE_INSERT_BLOB state.
In this case, step 4 is not correct. Because of step 1, the new
record need not own the blobs. Hence the assert failure.
Solution:
The assert in step 4 is removed. Instead code is added to ensure that
the record owns the blob.
Note:
This is a regression caused by rb#4479.
rb#4571 approved by Marko
Syntax. Server support. Test cases.
InnoDB bugfixes:
* don't mess around with system sprintf's, always use my_error() for errors.
* don't use InnoDB internal error codes where OS error codes are expected.
* don't say "file not found", when it was.
Update InnoDB to 5.6.14
Apply MySQL-5.6 hack for MySQL Bug#16434374
Move Aria-only HA_RTREE_INDEX from my_base.h to maria_def.h (breaks an assert in InnoDB)
Fix InnoDB memory leak
Problem:
The function row_upd_changes_ord_field_binary() is used to decide whether to
use row_upd_clust_rec_by_insert() or row_upd_clust_rec(). The function
row_upd_changes_ord_field_binary() does not make use of charset information.
Based on binary comparison it decides that r1 and r2 differ in their ordering
fields.
In the function row_upd_clust_rec_by_insert(), an update is done by delete +
insert. These operations internally make use of cmp_dtuple_rec_with_match()
to compare records r1 and r2. This comparison takes place with the use of
charset information.
This means that it is possible for the deleted record to be reused in the
subsequent insert. In the given scenario, the characters 'a' and 'A' are
considered equal in the my_charset_latin1. When this happens, the ownership
information of externally stored blobs are not correctly handled.
Solution:
When an update is done by delete followed by insert, disown the relevant
externally stored fields during the delete marking itself (within the same
mtr). If the insert succeeds, then nothing with respect to blob ownership
needs to be done. If the insert fails, then the disown done earlier will be
removed when the operation is rolled back.
rb#4479 approved by Marko.
Problem:
The function row_upd_changes_ord_field_binary() is used to decide whether to
use row_upd_clust_rec_by_insert() or row_upd_clust_rec(). The function
row_upd_changes_ord_field_binary() does not make use of charset information.
Based on binary comparison it decides that r1 and r2 differ in their ordering
fields.
In the function row_upd_clust_rec_by_insert(), an update is done by delete +
insert. These operations internally make use of cmp_dtuple_rec_with_match()
to compare records r1 and r2. This comparison takes place with the use of
charset information.
This means that it is possible for the deleted record to be reused in the
subsequent insert. In the given scenario, the characters 'a' and 'A' are
considered equal in the my_charset_latin1. When this happens, the ownership
information of externally stored blobs are not correctly handled.
Solution:
When an update is done by delete followed by insert, disown the relevant
externally stored fields during the delete marking itself (within the same
mtr). If the insert succeeds, then nothing with respect to blob ownership
needs to be done. If the insert fails, then the disown done earlier will be
removed when the operation is rolled back.
rb#4479 approved by Marko.
Also known as MySQL#70047 and BUG#17316314 (srv_buf_size not declared).
The workaround is taken from MySQL 5.6 tree:
BUG#17316314 - SRV_BUF_SIZE NOT DECLARED
Temporary fix. Disabling FALLOC_FL_PUNCH_HOLE for now
Regression from bug#14621190 due to disabled optimistic restoration
of cursor, which required full key lookup instead of verifying
if previously positioned btree cursor could be reused.
Fixed by enable optimistic restore and adjust cursor afterward.
rb#3324 approved by Marko.
