The MySQL DAYNAME function is a date and time function that is used to retrieve the name of the day of the week for a given date. It is particularly useful when you have a date value and you want to know the corresponding day of the week without having to manually interpret the date.

Syntax

Here is the basic syntax of the DAYNAME function:

DAYNAME(date)

date: This is the date for which you want to retrieve the day name.
The function takes a date as an argument and returns the name of the day for that date. The day name is returned as a string.

Example

Here is an example of how you might use the DAYNAME function:

SELECT DAYNAME('2024-01-01') AS DayOfWeek;

In this example, the DAYNAME function is used to retrieve the day of the week for the date ‘2024-01-01’. The result would be something like ‘Tuesday’, depending on the actual day of the week for that date.

It’s important to note that the day name is case-sensitive and is returned in the default language of the MySQL server. If you want to get the day name in a specific language, you can use the SET lc_time_names statement to set the language before executing the DAYNAME() function.

Here is an example of setting the language to Spanish and then using the DAYNAME function:

SET lc_time_names = 'es_ES';
SELECT DAYNAME('2024-01-01') AS DiaDeLaSemana;

In this case, the day name would be returned in Spanish, such as ‘martes’ for Tuesday.

In summary, the DAYNAME function in MySQL is a convenient way to retrieve the name of the day of the week for a given date, and it can be helpful in various scenarios where you need to work with date and time information in your database.