MySQL TO_DAYS Function Explained

The MySQL function TO_DAYS() is used to calculate the number of days from a given date to January 1st, year 0. It converts a date into an integer value, representing the number of days elapsed since January 1st, year 0.

The syntax of the function is as follows:

TO_DAYS(date)

The date parameter is a date value, which can be a date literal, a date-time column, or a string representing a date, such as ‘2022-01-01’.

The following is an example demonstrating how to use the TO_DAYS() function to calculate the number of days between a given date and January 1st, year 0.

SELECT TO_DAYS('2022-01-01'); -- 返回 737791

The TO_DAYS() function is commonly used in practical applications to calculate the difference between dates, such as determining the number of days between two specific dates.

It is important to note that the TO_DAYS() function defaults to using the Gregorian calendar as the calculation basis.