hour
1. HOUR Function
=======hour
1. HOUR Function
>>>>>>> 9d19b1c8cb744c8e86d5c15b74d8b5f719ad62beThe HOUR function in H2 database is used to extract the hour component from a given time or timestamp value.
2. Syntax
The syntax for the HOUR function in H2 database is as follows:
HOUR(time)
Arguments
time
: The time or timestamp value from which the hour component needs to be extracted. It should be a valid time or timestamp value.
Return
- The HOUR function returns the hour component of the given time or timestamp value as an integer.
3. Notes
- The HOUR function in H2 database extracts the hour value from the time or timestamp value, ranging from 0 to 23.
- If the input value is not a valid time or timestamp, the HOUR function will return
NULL
. - Ensure that the input value is in the correct format and datatype to avoid errors while using the HOUR function.
4. Examples
Here are a few examples demonstrating the usage of the HOUR function in H2 database:
Example 1 - Extracting the hour from a time value:
SELECT HOUR(TIME '10:30:45') AS hour;
Output:
hour
----
10
Example 2 - Extracting the hour from a timestamp value:
SELECT HOUR(TIMESTAMP '2022-01-01 18:45:30') AS hour;
Output:
hour
----
18
Example 3 - Extracting the hour from a column:
CREATE TABLE events (
id INT PRIMARY KEY,
event_time TIMESTAMP
);
INSERT INTO events VALUES (1, TIMESTAMP '2022-01-01 12:30:00'), (2, TIMESTAMP '2022-01-01 23:15:00');
SELECT id, event_time, HOUR(event_time) AS hour
FROM events;
Output:
id | event_time | hour
---+----------------------------+------
1 | 2022-01-01 12:30:00.000000 | 12
2 | 2022-01-01 23:15:00.000000 | 23