Skip to main content

iso_day_of_week

1. ISO_DAY_OF_WEEK Function​

The ISO_DAY_OF_WEEK function in H2 database is used to retrieve the ISO day of the week for a given date.

2. Syntax​

The syntax for the ISO_DAY_OF_WEEK function in H2 database is as follows:

ISO_DAY_OF_WEEK(date)

Arguments​

  • date: The date for which the ISO day of the week needs to be determined. It should be a valid date value.

Return​

  • The ISO_DAY_OF_WEEK function returns an integer representing the ISO day of the week for the given date. The ISO day of the week ranges from 1 (Monday) to 7 (Sunday).

3. Notes​

  • The ISO_DAY_OF_WEEK function in H2 database follows the ISO-8601 standard for determining the day of the week. According to this standard, Monday is considered the first day of the week.
  • The input date should be a valid date value in the format 'YYYY-MM-DD'. If the input is not a valid date or is in a different format, the ISO_DAY_OF_WEEK function will return NULL.
  • Ensure that the input date is within the supported range of the H2 database.

4. Examples​

Here are a few examples demonstrating the usage of the ISO_DAY_OF_WEEK function in H2 database:

Example 1 - Retrieving the ISO day of the week for a specific date:​

SELECT ISO_DAY_OF_WEEK('2022-01-01') AS iso_day;

Output:

iso_day
-------
6

Example 2 - Retrieving the ISO day of the week for dates stored in a table:​

CREATE TABLE events (
  id INT PRIMARY KEY,
  event_date DATE
);

INSERT INTO events VALUES (1, '2022-01-01'), (2, '2022-01-05'), (3, '2022-01-10');

SELECT id, event_date, ISO_DAY_OF_WEEK(event_date) AS iso_day
FROM events;

Output:

id | event_date  | iso_day
---+-------------+--------
1  | 2022-01-01  | 6
2  | 2022-01-05  | 3
3  | 2022-01-10  | 1
  • day_of_week - Calculate day of the week (Sunday = 1, Monday = 2, etc.)
  • DAY_NAME - Retrieve the name of the day of the week