How to Retrieve Records for the Current Week in MySQL Using YEARWEEK()?

MySQL: Retrieving Records for the Current Week

This question revolves around retrieving records from a MySQL table based on a specific time period within the current week. Let's explore the provided algorithm and a more efficient MySQL query to achieve this task.

The initial algorithm involved calculating the weekday, determining the date of the previous Monday, then fetching records within a defined date range. While this algorithm works, it requires multiple steps and calculations.

Fortunately, MySQL provides built-in functions that can simplify this process. The YEARWEEK() function, particularly with the parameter '1', allows you to determine the week number of a given date and year.

Efficient Query Using YEARWEEK()

The following query utilizes the YEARWEEK() function to retrieve records for the current week:

SELECT *
FROM   temp
WHERE  YEARWEEK(`date`, 1) = YEARWEEK(CURDATE(), 1)

Understanding the Query

• YEARWEEK() calculates the week number of a given date, taking into account the week's starting day (Monday for parameter '1').
• CURDATE() retrieves the current date.
• The query then filters records where the YEARWEEK() value of the date column matches the YEARWEEK() value of the current date.

Addressing the Additional Question

The query provided in the question does not accurately select records for the week starting from Monday. It includes Sunday from the previous week as Monday is considered day 1 of the week (ISO format). To rectify this, we can modify the query as follows:

SELECT *
FROM   temp
WHERE  YEARWEEK(`date`, 7) = YEARWEEK(CURDATE(), 7)

Summary

The YEARWEEK() function provides a simple and efficient way to select records based on week numbers in MySQL. It eliminates the need for complex calculations and intermediate steps. By understanding the YEARWEEK() function, you can easily obtain records for the current week or specific time periods within a year.

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