On an environment with more thatn 500000 tables, the mysqldump is slow on dumping separate tables.

mysqldump uses the traditional queries like

show table status like 'a\_test\_bgtable\_2';

SHOW TRIGGERS LIKE ''a\_test\_bgtable\_2';

SHOW TABLES LIKE ''a\_test\_bgtable\_2';

instead of querying information_schema.tables .

select *

from information_schema.tables

where table_schema = 'test_tmp'

and table_name = 'a_test_bgtable_2';

takes 0.0011s, while

use test_tmp;

show tables like 'a\_test\_bgtable\_2';

takes about 10 seconds. This makes the dumps unnecessary slow.

mysqldump could use the information_schema here (after checking the server version), or the server could detect LIKE-Patterns that can only expand to exactly one table name (because there are no wildcards) and use a more intelligent algorithm internally, e.g. use the implementation of information_schema.tables .