10.1.8-MariaDB-1~precise mariadb.org binary distribution (ubuntu)

bala.linux, are you using MyISAM engine for the table?

For now I'll assume you are.

--source include/have_partition.inc

create table t1 (i int) engine=MyISAM partition by hash(i) partitions 2;

alter table t1 comment 'test', algorithm=inplace;

drop table t1;

MariaDB [test]> alter table t1 comment 'test', algorithm=inplace;

ERROR 1845 (0A000): ALGORITHM=INPLACE is not supported for this operation. Try ALGORITHM=COPY.

Works okay with InnoDB and without partitioning.
Reproducible on MySQL 5.6.10, but apparently it was fixed in MySQL 5.6.11 – the release notes have this:

Partitioning: ALGORITHM = INPLACE, which was disallowed in MySQL 5.6.10 for DDL statements operating on partitioned tables, can once again be used with such statements. (Bug #16216513)

References: See also Bug #14760210.

Maybe we got the InnoDB part of the fix with regular InnoDB merges, but MyISAM still has the problem.

Yes. We are using MyISAM with partitioning.

Team,

Looks like this hasn't got fixed yet. I tried the test case from comment #1 and it failed to work. Please check.

mysql> show variables like '%version%';

+-------------------------+---------------------------------+

| Variable_name           | Value                           |

+-------------------------+---------------------------------+

| innodb_version          | 5.6.28-76.1                     |

| protocol_version        | 10                              |

| slave_type_conversions  |                                 |

| version                 | 10.0.24-MariaDB-1~trusty        |

| version_comment         | mariadb.org binary distribution |

| version_compile_machine | x86_64                          |

| version_compile_os      | debian-linux-gnu                |

| version_malloc_library  | bundled jemalloc                |

+-------------------------+---------------------------------+

8 rows in set (0.00 sec)

mysql> create table t1 (i int) engine=MyISAM partition by hash(i) partitions 2;

Query OK, 0 rows affected (0.00 sec)

mysql> alter table t1 comment 'test', algorithm=inplace;

ERROR 1845 (0A000): ALGORITHM=INPLACE is not supported for this operation. Try ALGORITHM=COPY.

mysql>

Thanks.

-Bala

serg, see above ^
I see the commit related to this bug report, but maybe you only pushed a part of the patch? I don't see the test case for MyISAM/partition there.

bala.linux, you're right. This was fixed only for not partitioned table. I'm sorry for this.
I've now created a new MDEV-9868 specifically for partitioned tables, it will be fixed in the next release.

Thanks. Also, would it be possible to do something similar for altering "column" comments ? It does the full copy too. I created MDEV-9168 but never got any attention. Please let me know.

-Bala

MDEV-9168 is a Task listing two distinct issues: the awkward syntax and a full table copy.
If you'd like I can convert it to a Bug about full table copy when altering column comments.
Alternatively, you can create a new bug report for the latter and keep the task to deal with the awkward syntax.

Yes. Please convert it to a bug to track "full table copy when altering column comments". I created a new bug for the awkward syntax (MDEV-9878).

Thanks.

-Bala