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How does table locking work in MySQL server?
MySQL allows a client session to acquire a table lock explicitly to cooperate with other sessions to access the table’s data. MySQL also allows table locking to prevent it from unauthorized modification into the same table during a specific period. A session in MySQL can acquire or release locks on the table only for itself.
How to release the read lock in MySQL?
From the first session, use the SHOW PROCESSLIST statement to show detailed information: After that, go back to the first session and release the lock by using the UNLOCK TABLES statement. After you release the READ lock from the first session, the INSERT operation in the second session executed.
What happens when you drop a table in MySQL?
The TEMPORARY option allows you to remove temporary tables only. It ensures that you do not accidentally remove non-temporary tables. The IF EXISTS option conditionally drop a table only if it exists. If you drop a non-existing table with the IF EXISTS option, MySQL generates a NOTE, which can be retrieved using the SHOW WARNINGS statement.
What does the lock flag mean in MySQL?
A lock is a flag associated with a table. MySQL allows a client session to explicitly acquire a table lock for preventing other sessions from accessing the same table during a specific period.
What are the two types of lock in MySQL?
MySQL provides two types of locks onto the table, which are: READ LOCK: This lock allows a user to only read the data from a table. WRITE LOCK: This lock allows a user to do both reading and writing into a table. It is to note that the default storage engine used in MySQL is InnoDB.
When do you disable a trigger in MySQL?
DISABLE, the trigger is disabled forever, or until the next ALTER ENABLE occurs. A disabled trigger continues to exist and is visible, but is never activated by statements like insert, update, or delete. If a trigger is already disabled, ALTER