How to Add Two Hours to the Current Time in a MySQL Query?

Extending Time by Two Hours in MySQL

In MySQL, you may encounter the need to manipulate time values in your queries. One common scenario is adding a specific duration to the current time.

Original Query

The following query attempts to retrieve rows where the start_time field of the courses table is less than the current time offset by two hours:

SELECT * FROM courses WHERE (now() + 2 hours) > start_time

Syntax Error

However, this syntax is invalid in MySQL. The now() function returns a timestamp, and directly adding hours to it is not supported.

Corrected Query

To correctly add 2 hours to the current time in MySQL, use the DATE_ADD() function:

SELECT * 
FROM courses 
WHERE DATE_ADD(NOW(), INTERVAL 2 HOUR) > start_time

The DATE_ADD() function takes two arguments: the timestamp to be modified (in this case, NOW()) and an INTERVAL specifying the duration and unit of time to be added. In this case, INTERVAL 2 HOUR adds two hours to the current time.

Additional Notes

The DATE_ADD() function provides versatile date and time manipulation capabilities. It supports various intervals, including days, months, and years. Refer to MySQL documentation for more details on date and time functions.

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