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15 commits

Author SHA1 Message Date
Kristian Nielsen
34f11b06e6 Move deletion of old GTID rows to slave background thread
This patch changes how old rows in mysql.gtid_slave_pos* tables are deleted.
Instead of doing it as part of every replicated transaction in
record_gtid(), it is done periodically (every @@gtid_cleanup_batch_size
transaction) in the slave background thread.

This removes the deletion step from the replication process in SQL or worker
threads, which could speed up replication with many small transactions. It
also decreases contention on the global mutex LOCK_slave_state. And it
simplifies the logic, eg. when a replicated transaction fails after having
deleted old rows.

With this patch, the deletion of old GTID rows happens asynchroneously and
slightly non-deterministic. Thus the number of old rows in
mysql.gtid_slave_pos can temporarily exceed @@gtid_cleanup_batch_size. But
all old rows will be deleted eventually after sufficiently many new GTIDs
have been replicated.
2018-12-07 07:10:40 +01:00
Alexander Barkov
4447a02cf1 MDEV-16991 Rounding vs truncation for TIME, DATETIME, TIMESTAMP 2018-11-26 08:10:47 +04:00
Marko Mäkelä
c761b43451 Merge 10.3 into 10.4 2018-11-08 10:19:55 +02:00
Vladislav Vaintroub
564a63b5a3 MDEV-14429 sql_safe_updates in my.cnf not work 2018-11-06 13:36:50 +01:00
Marko Mäkelä
1bf3e8ab43 Merge 10.3 into 10.4 2018-09-11 21:31:03 +03:00
Marko Mäkelä
7830fb7f45 Merge 10.2 into 10.3 2018-08-28 12:22:56 +03:00
Vladislav Vaintroub
077e590bbc MDEV-16277 : Adjust MTR test results. 2018-08-12 00:13:19 +01:00
Igor Babaev
cab1d63826 Merge branch '10.3' into 10.4 2018-06-03 10:34:41 -07:00
Galina Shalygina
d3ff133390 MDEV-12387 Push conditions into materialized subqueries
The logic and the implementation scheme are similar with the
MDEV-9197 Pushdown conditions into non-mergeable views/derived tables

How the push down is made on the example:

select * from t1
where a>3 and b>10 and
 (a,b) in (select x,max(y) from t2 group by x);

-->

select * from t1
where a>3 and b>10 and
  (a,b) in (select x,max(y)
            from t2
            where x>3
            group by x
            having max(y)>10);

The implementation scheme:

1. Search for the condition cond that depends only on the fields
   from the left part of the IN subquery (left_part)
2. Find fields F_group in the select of the right part of the
   IN subquery (right_part) that are used in the GROUP BY
3. Extract from the cond condition cond_where that depends only on the
   fields from the left_part that stay at the same places in the left_part
   (have the same indexes) as the F_group fields in the projection of the
   right_part
4. Transform cond_where so it can be pushed into the WHERE clause of the
   right_part and delete cond_where from the cond
5. Transform cond so it can be pushed into the HAVING clause of the right_part

The optimization is made in the
Item_in_subselect::pushdown_cond_for_in_subquery() and is controlled by the
variable condition_pushdown_for_subquery.

New test file in_subq_cond_pushdown.test is created.

There are also some changes made for setup_jtbm_semi_joins().
Now it is decomposed into the 2 procedures: setup_degenerate_jtbm_semi_joins()
that is called before optimize_cond() for cond and setup_jtbm_semi_joins()
that is called after optimize_cond().
New setup_jtbm_semi_joins() is made in the way so that the result of its work is
the same as if it was called before optimize_cond().

The code that is common for pushdown into materialized derived and into materialized
IN subqueries is factored out into pushdown_cond_for_derived(),
Item_in_subselect::pushdown_cond_for_in_subquery() and
st_select_lex::pushdown_cond_into_where_clause().
2018-05-15 23:45:59 +02:00
Eugene Kosov
da25860d4a MDEV-15995 Drop extra semicolon in VARIABLE_COMMENT for SYSTEM_VERSIONING_ALTER_HISTORY 2018-05-12 10:16:46 +02:00
Sergei Golubchik
4203f572ae MDEV-15923 option to control who can set session @@timestamp
--secure-timestamp=NO|SUPER|REPLICATION|YES
2018-05-12 10:16:45 +02:00
Thirunarayanan Balathandayuthapani
85cc6b70bd MDEV-13134 Introduce ALTER TABLE attributes ALGORITHM=NOCOPY and ALGORITHM=INSTANT
Introduced new alter algorithm type called NOCOPY & INSTANT for
inplace alter operation.

NOCOPY - Algorithm refuses any alter operation that would
rebuild the clustered index. It is a subset of INPLACE algorithm.

INSTANT - Algorithm allow any alter operation that would
modify only meta data. It is a subset of NOCOPY algorithm.

Introduce new variable called alter_algorithm. The values are
DEFAULT(0), COPY(1), INPLACE(2), NOCOPY(3), INSTANT(4)

Message to deprecate old_alter_table variable and make it alias
for alter_algorithm variable.

alter_algorithm variable for slave is always set to default.
2018-05-07 14:58:11 +05:30
Marko Mäkelä
7396dfcca7 Merge 10.2 into 10.3 2018-04-24 20:59:57 +03:00
Vicențiu Ciorbaru
65eefcdc60 Merge remote-tracking branch '10.2' into 10.3 2018-04-12 12:41:19 +03:00
Michael Widenius
a7abddeffa Create 'main' test directory and move 't' and 'r' there 2018-03-29 13:59:44 +03:00
Renamed from mysql-test/r/mysqld--help.result (Browse further)