The problem is the async binlog checkpointing; this could on rare
occasions occur too late, causing SHOW BINLOG EVENTS to show the
wrong events and cause .result file difference.
back-ported the patch for bug #13256831 from mysql-5.6 code line.
Here's the comment this patch was provided with:
Fixed bug#13256831 - ERROR 1032 (HY000): CAN'T FIND RECORD.
This bug only occurs if a user tries to update a base table using
an updatable view and this view was created as a join for which
the clause 'WITH CHECK OPTION' was specified.
The reason for the bug was that when such an update was
executed, row positions were not properly handled for tables
that were not updated but had constraints that had to be
checked due to the 'WITH CHECK OPTION' clause.
The reason for the bug was that when such update is executed
then for tables specified in the view definition and
also listed in the 'WITH CHECK OPTION' clause the positioning to
row being updated is not performed.
Both bugs are caused by the same problem: the function optimize_cond() should
update the value of *cond_equal rather than the value of join->cond_equal,
because it is called not only for the WHERE condition, but for the HAVING
condition as well.
option leaves the database in inconsistent state,
Analysis: Problem was that atomic writes variable had incorrect
type on same places leading to fact that e.g. OFF option was
not regognized. Furthermore, some error check code was missing
from both InnoDB and XtraDB engines. Finally, when table is
created we have already created the .ibd file and if we can't
set atomic writes it stays there.
Fix: Fix atomic writes variable type to ulint as it should be.
Fix: Add proper error code checking on os errors on both InnoDB
and XtraDB
Fix: Remove the .idb file when atomic writes can't be enabled
to a new table.
WRITTEN WHILE ROWS REMAINS
Problem:
========
When truncate table fails while using transactional based
engines even though the operation errors out we still
continue and log it to binlog. Because of this master has
data but the truncate will be written to binary log which
will cause inconsistency.
Analysis:
========
Truncate table can happen either through drop and create of
table or by deleting rows. In the second case the existing
code is written in such a way that even if an error occurs
the truncate statement will always be binlogged. Which is not
correct.
Binlogging of TRUNCATE TABLE statement should check whether
truncate is executed "transactionally or not". If the table
is transaction based we log the TRUNCATE TABLE only on
successful completion.
If table is non transactional there are possibilities that on
error we could have partial changes done hence in such cases
we do log in spite of errors as some of the lines might have
been removed, so the statement has to be sent to slave.
Fix:
===
Using table handler whether truncate table is being executed
in transaction based mode or not is identified and statement
is binlogged accordingly.
mysql-test/suite/binlog/r/binlog_truncate_kill.result:
Added test case to test the fix for Bug#17942050.
mysql-test/suite/binlog/t/binlog_truncate_kill.test:
Added test case to test the fix for Bug#17942050.
sql/sql_truncate.cc:
Check if truncation is successful or not and retun appropriate
return values so that binlogging can be done based on that.
sql/sql_truncate.h:
Added a new enum.
catalog data path had not been set. This was added into ha_connect::info.
modified:
storage/connect/ha_connect.cc
- All the functions querying table options could return information from the wrong
table when several CONNECT tables were used in the same query (for instance joined
together) This was because they belonged to the catalog class that is shared between
all tables in the same query. They have been moved from the catalog class to the
TABDEF/RELDEF class that is attached to each table. This was a major potential bug.
modified:
storage/connect/catalog.h
storage/connect/filamvct.cpp
storage/connect/filamzip.cpp
storage/connect/mycat.cc
storage/connect/mycat.h
storage/connect/reldef.cpp
storage/connect/reldef.h
storage/connect/tabdos.cpp
storage/connect/tabfmt.cpp
storage/connect/tabmul.cpp
storage/connect/tabmysql.cpp
storage/connect/taboccur.cpp
storage/connect/tabodbc.cpp
storage/connect/tabpivot.cpp
storage/connect/tabsys.cpp
storage/connect/tabtbl.cpp
storage/connect/tabutil.cpp
storage/connect/tabvct.cpp
storage/connect/tabwmi.cpp
storage/connect/tabxcl.cpp
storage/connect/tabxml.cpp
storage/connect/xindex.cpp
- Prepare indexing of MYSQL/ODBC tables (as does FEDERATED) (Not implemented yet)
modified:
storage/connect/ha_connect.cc
storage/connect/ha_connect.h
storage/connect/mycat.cc
storage/connect/mycat.h
- Typo
modified:
storage/connect/plgdbutl.cpp
Add a testcase and backport this fix:
Bug#14338686: MYSQL IS GENERATING DIFFERENT AND SLOWER
(IN NEWER VERSIONS) EXECUTION PLAN
PROBLEM:
While checking for an index to sort for the order by clause
in this query
"SELECT datestamp FROM contractStatusHistory WHERE
contract_id = contracts.id ORDER BY datestamp asc limit 1;"
we do not calculate the number of rows to be examined correctly.
As a result we choose index 'idx_contractStatusHistory_datestamp'
defined on the 'datestamp' field, rather than choosing index
'contract_id'. And hence the lower performance.
ANALYSIS:
While checking if an index is present to give the records in
sorted order(datestamp), we consider the selectivity of the
'ref_key'(contract_id here) using 'table->quick_condition_rows'.
'ref_key' here can be an index from 'REF_ACCESS' or from 'RANGE'.
As this is a 'REF_ACCESS', 'table->quick_condition_rows' is not
set to the actual value which is 2. Instead is set to the number
of tuples present in the table indicating that every row that
is selected would be satisfying the condition present in the query.
Hence, the selectivity becomes 1 even when we choose the index
on the order by column instead of the join_condition.
But, in reality as only 2 rows satisy the condition, we need to
examine half of the entire data set to get one tuple when we
choose index on the order by column.
Had we chosen the 'REF_ACCESS' we would have examined only 2 tuples.
Hence the delay in executing the query specified.
FIX:
While calculating the selectivity of the ref_key:
For REF_ACCESS consider quick_rows[ref_key] if range
optimizer has an estimate for this key. Else consider
'rec_per_key' statistic.
For RANGE ACCESS consider 'table->quick_condition_rows'.
Revert the old patch revid:monty@askmonty.org-20100325133339-7mkel6valai0b4lb
This patch caused the InnoDB part of the transaction to not be marked
read-write in some cases, which messes up XA commit (and likely other
stuff as well).
The problem was in the validation of the input data for blob types.
When assigned binary data, the character blob types were only checking if
the length of these data is a multiple of the minimum char length for the
destination charset.
And since e.g. UTF-8's minimum character length is 1 (becuase it's
variable length) even byte sequences that are invalid utf-8 strings (e.g.
wrong leading byte etc) were copied verbatim into utf-8 columns when
coming from binary strings or fields.
Storing invalid data into string columns was having all kinds of ill effects
on code that assumed that the encoding data are valid to begin with.
Fixed by additionally checking the incoming binary string for validity when
assigning it to a non-binary string column.
Made sure the conversions to charsets with no known "invalid" ranges
are not covered by the extra check.
Removed trailing spaces.
Test case added.
The problem was that the view substitute its fields (on prepare) with reverting the change after execution. After prepare on optimization exists2in convertion substituted arguments of '=' with constsnt '1', but then one of the arguments of '=' was reverted to the view field reference.This lead to incorrect WHERE condition on the second execution.
To fix the problem we replace whole '=' with '1' permannently.
We need to use mysql_cond_broadcast() rather than _signal for
COND_thread_count, as there can be multiple waiters.
Thanks to Pavel Ivanov for reporting both the problem and the
solution.
archive table which is using an auto increment column, the
server hangs. In order to recover the mysqld process, it
has to be terminated abnormally using SIGKILL. The problem
is observed in mysql-5.5.
Bug #18065452 "PREPARING" STATE HOGS CPU WITH ARCHIVE
+ SUBQUERY
Analysis: This happens because the server is trapped inside
an infinite loop in the function,
"subselect_indexsubquery_engine::exec()". This function
resolves the correlated suquery by doing an index lookup
for the appropriate engine. In case of archive engine,
after reaching the end of records, "table->status" is not
set to STATUS_NOT_FOUND. As a result the loop is not
terminated.
Fix: The "table->status" is set to STATUS_NOT_FOUND when
the end of records is reached.
modified:
storage/connect/ha_connect.cc
storage/connect/ha_connect.h
storage/connect/xindex.cpp
- Optimize retrieving numeric values in scan_record. Was previously
translating numeric values to character representation back and forth.
modified:
storage/connect/ha_connect.cc
storage/connect/mysql-test/connect/r/xml.result
- Modify Pivot table creation to avoid reading the entire source table
when making columns from Discovery. MDEV-6024
modified:
storage/connect/tabpivot.cpp
