lock_timeout
1. LOCK_TIMEOUT Function
=======lock_timeout
1. LOCK_TIMEOUT Function
>>>>>>> 9d19b1c8cb744c8e86d5c15b74d8b5f719ad62beThe LOCK_TIMEOUT function in H2 database is used to set the timeout value for waiting to acquire a lock on a database object.
2. Syntax
The syntax for the LOCK_TIMEOUT function in H2 database is as follows:
LOCK_TIMEOUT(timeout)
Arguments
timeout
: The timeout value in milliseconds. It should be a positive integer representing the number of milliseconds to wait for acquiring a lock.
Return
- The LOCK_TIMEOUT function does not return any value. It is used to set the timeout value for lock acquisition.
3. Notes
- The LOCK_TIMEOUT function in H2 database is used to set the timeout value globally for the current session.
- When a database object is locked, other sessions attempting to acquire a lock on the same object will wait for the specified timeout period. If the lock cannot be acquired within the timeout, an exception will be thrown.
- Specifying a value of 0 for the timeout means that the lock acquisition will not wait and will throw an exception immediately if the lock cannot be acquired.
- The timeout value set using the LOCK_TIMEOUT function affects all subsequent lock acquisition operations within the session.
4. Examples
Here are a few examples demonstrating the usage of the LOCK_TIMEOUT function in H2 database:
Example 1 - Setting the lock timeout value to 5000 milliseconds:
LOCK_TIMEOUT(5000);
In this example, the lock timeout value is set to 5000 milliseconds (5 seconds) for the current session. Any subsequent lock acquisition operations will wait for a maximum of 5 seconds to acquire the lock before throwing an exception.
Example 2 - Setting the lock timeout value to 0 milliseconds:
LOCK_TIMEOUT(0);
In this example, the lock timeout value is set to 0 milliseconds for the current session. Any subsequent lock acquisition operations will not wait and will throw an exception immediately if the lock cannot be acquired.
Example 3 - Retrieving the current lock timeout value:
SELECT LOCK_TIMEOUT() AS current_timeout;
In this example, the current lock timeout value is retrieved using the LOCK_TIMEOUT function. The value will be returned as the result of the query.
5. Related Functions
There are no related functions specifically related to the LOCK_TIMEOUT function in H2 database.