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
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
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.
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.
Analysis: After ALTER TABLE the table statistics needs to be rebuilt and therefore stat_initialized is set false. It will be rebuilt when the table is loaded again and table is closed when alter table is completed. However, during alter table table could be used by concurrent SELECT from I_S. Therefore, we need to rebuild transient table statistics meanwhile until table can be reloaded.
INDEX_READ_MAP HAD NO MATCH
If index_read_map is called for exact search and no matching records
exists it will position the cursor on the next record, but still having the
relative position to BTR_PCUR_ON.
This will make a call for index_next to read yet another next record,
instead of returning the record the cursor points to.
Fixed by setting pcur->rel_pos = BTR_PCUR_BEFORE if an exact
[prefix] search is done, but failed.
Also avoids optimistic restoration if rel_pos != BTR_PCUR_ON,
since btr_cur may be different than old_rec.
rb#3324, approved by Marko and Jimmy
DICT_TABLE_GET_FORMAT(CLUST_INDEX->TABLE) >= 1
The function row_sel_sec_rec_is_for_clust_rec() was incorrectly
preparing to compare a NULL column prefix in a secondary index with a
non-NULL column in a clustered index.
This can trigger an assertion failure in 5.1 plugin and later. In the
built-in InnoDB of MySQL 5.1 and earlier, we would apparently only do
some extra work, by trimming the clustered index field for the
comparison.
The code might actually have worked properly apart from this debug
assertion failure. It is merely doing some extra work in fetching a
BLOB column, and then comparing it to NULL (which would return the
same result, no matter what the BLOB contents is).
While the test case involves CHECK TABLE, this could theoretically
occur during any read that uses a secondary index on a column prefix
of a column that can be NULL.
rb#3101 approved by Mattias Jonsson
There was a race condition in the rollback of TRX_UNDO_UPD_DEL_REC.
Once row_undo_mod_clust() has rolled back the changes by the rolling-back
transaction, it attempts to purge the delete-marked record, if possible, in a
separate mini-transaction.
However, row_undo_mod_remove_clust_low() fails to check if the DB_TRX_ID of
the record that it found after repositioning the cursor, is still the same.
If it is not, it means that the record was purged and another record was
inserted in its place.
So, the rollback would have performed an incorrect purge, breaking the
locking rules and causing corruption.
The problem was found by creating a table that contains a unique
secondary index and a primary key, and two threads running REPLACE
with only one value for the unique column, so that the uniqueness
constraint would be violated all the time, leading to statement
rollback.
This bug exists in all InnoDB versions (I checked MySQL 3.23.53).
It has become easier to repeat in 5.5 and 5.6 thanks to scalability
improvements and a dedicated purge thread.
rb#3085 approved by Jimmy Yang
Problem:
When the user specified foreign key name contains "_ibfk_", InnoDB wrongly
tries to rename it.
Solution:
When a table is renamed, all its associated foreign keys will also be renamed,
only if the foreign key names are automatically generated. If the foreign key
names are given by the user, even if it has _ibfk_ in it, it must not be
renamed.
rb#2935 approved by Jimmy, Krunal and Satya