Sergei Petrunia added a comment - 2016-11-21 18:18 The table being altered is partitioned: CREATE TABLE t1 (i INT, j INT, k INT, PRIMARY KEY (i), KEY(j)) ENGINE = ROCKSDB PARTITION BY KEY(i) PARTITIONS 4; ... ALTER TABLE t1 ADD INDEX kij(i,j), ALGORITHM=INPLACE;

Sergei Petrunia added a comment - 2016-11-21 18:21 The difference starts in ha_rocksdb::check_if_supported_inplace_alter() . ha_alter_info->handler_flags value is different. fb/mysql-5.6 has value 1 which is // Add non-unique, non-primary index static const HA_ALTER_FLAGS ADD_INDEX = 1L << 0; MariaDB has $108 = 0x80000001 which is // Add non-unique, non-primary index static const HA_ALTER_FLAGS ADD_INDEX = 1L << 0; ... /** ALTER TABLE for a partitioned table. The engine needs to commit online alter of all partitions atomically (using group_commit_ctx) */ static const HA_ALTER_FLAGS ALTER_PARTITIONED = 1L << 31; fb/mysql-5.6 doesn't have ALTER_PARTITIONED defined (neither do mysql-5.6, nor mysql-5.7)

Sergei Petrunia added a comment - 2016-11-21 18:24 - edited Relevant commits: https://github.com/MariaDB/server/commit/97728e107a5262266a2f6ed61bae9639a1717831 https://github.com/MariaDB/server/commit/99027efd14f9f3a66dcc32d6313a4c4ed71bffe8 https://github.com/MariaDB/server/commit/9927b36e87652c6dc4ff2425e86570d678bac224

Sergei Petrunia added a comment - 2016-12-04 09:30 Fixed in work tree