Hi had checked the "show processlist" and this query is running there and multiple time it's running problem is that it is scanning all rows, means not in optimize state and if it is auto generated query then how we can pass the partition information. and this query is not run by user, they are running optimize query it seems it taking some metadata from mysql, something like below..... So that's why i was thinking it meta generated query.  | id | select_type | table | partitions | type  | possible_keys                    | key             | key_len | ref         | rows    | filtered | Extra       | +----+-------------+-------+------------+-------+----------------------------------+-----------------+---------+-------------+---------+----------+-------------+ |  1 | SIMPLE      | C0    | NULL       | const | PRIMARY,UNIQUE_DATABASE,CTLG_FK1 | UNIQUE_DATABASE | 389     | const,const |       1 |   100.00 | Using index | |  1 | SIMPLE      | B0    | NULL       | const | PRIMARY,UNIQUETABLE,TBLS_N49     | UNIQUETABLE     | 268     | const,const |       1 |   100.00 | Using index | |  1 | SIMPLE      | A0    | NULL       | ref   | PARTITIONS_N49                   | PARTITIONS_N49  | 9       | const       | 5555098 |    11.11 | Using where ... View more