Find the locked tables in MySQL Database
Syntax for identified locked tables in MySQL
SHOW OPEN TABLES [{FROM | IN} db_name]
[LIKE 'pattern' | WHERE expr]
Check all locked tables in MySQL Database
show open tables;
mysql> show open tables;
+--------------------+----------------------------+--------+-------------+
| Database | Table | In_use | Name_locked |
+--------------------+----------------------------+--------+-------------+
| mysql | check_constraints | 0 | 0 |
| sakila | customer | 1 | 0 |
| mysql | column_type_elements | 2 | 0 |
+--------------------+----------------------------+--------+-------------+
Note:
IN_USE column indicates of the table is locked. 0 means table is open, currently no one used, 1 means table is locked, its incremented if some one else lock then its value 2.
NAME_LOCKED column indicates whether the table name is locked, is used for drop ping or renaming tables request.
Check locked tables for particular database
mysql> show open tables in world;
+----------+-----------------+--------+-------------+
| Database | Table | In_use | Name_locked |
+----------+-----------------+--------+-------------+
| world | countrylanguage | 0 | 0 |
+----------+-----------------+--------+-------------+
1 row in set (0.00 sec)
Note: WORLD is database in MySQL
Check the locked tables having in_use value greater than 1
show open tables where in_use > 1;
mysql> show open tables where in_use > 1;
Empty set (0.00 sec)
Check the locked tables with its name.
show open tables like 'country';
mysql> show open tables like 'country';
+----------+---------+--------+-------------+
| Database | Table | In_use | Name_locked |
+----------+---------+--------+-------------+
| sakila | country | 0 | 0 |
+----------+---------+--------+-------------+
1 row in set (0.00 sec)
mysql> show open tables like 'country%';
+----------+-----------------+--------+-------------+
| Database | Table | In_use | Name_locked |
+----------+-----------------+--------+-------------+
| sakila | country | 0 | 0 |
| world | countrylanguage | 0 | 0 |
+----------+-----------------+--------+-------------+
2 rows in set (0.00 sec)