How to Extract the Week Number From a Date in SQL
To find the week number of a particular date in your database, use the SQLWEEK() function. This function takes a single argument, which is the date you want to extract the week number from. For example, if you wanted to extract the week number from the date 2020-10-01, you would use the following query:
SELECT WEEK('2020-10-01');Examples
Let's look at a few examples of how this function can be used. Suppose you have a table called orders with the following data:
| order_date | order_total |
|---|---|
| 2020-09-30 | 100 |
| 2020-10-01 | 200 |
| 2020-10-02 | 300 |
| 2020-10-03 | 400 |
If you wanted to extract the week number from the order_date column, you would use the following query:
SELECT WEEK(order_date) FROM orders;This query would return the results 40, 41, 41, and 41, since all of the dates are in the same week (week 41 of 2020).
Additional Info
The WEEK() function is supported by most major databases, including MySQL, PostgreSQL, and SQL Server. However, the syntax may vary slightly depending on the database you are using. For more information, check out the documentation for your particular database.
