How to Configure DATETIME Format During Table Creation in MySQL
Creating a table with a DATETIME column is a common task in MySQL. However, you may encounter situations where you want to specify a specific format for the DATETIME values. This article explains how to set the default format for a DATETIME column to 'DD-MM-YYYY HH:MM:SS' during table creation using MySQL commands.
Default MySQL DATETIME Format
By default, MySQL stores and retrieves DATETIME values in the 'YYYY-MM-DD HH:MM:SS' format. This is the standard format used by MySQL and is often appropriate for many applications.
Specifying a Custom Format
To specify a custom format for a DATETIME column during table creation, you can use the TIME_FORMAT function. The following MySQL command demonstrates how to create a table with a DATETIME column formatted as 'DD-MM-YYYY HH:MM:SS':
CREATE TABLE my_table ( id INT NOT NULL AUTO_INCREMENT, datetime_column DATETIME FORMAT TIME_FORMAT('%d-%m-%Y %H:%i:%s') );
In this command, the TIME_FORMAT specifier is used to define the custom 'DD-MM-YYYY HH:MM:SS' format.
Note: The TIME_FORMAT function only affects the representation of DATETIME values stored in the database. The actual DATETIME values are still stored in the 'YYYY-MM-DD HH:MM:SS' format.
Displaying the Formatted Value
Once the table is created, you can use the DATE_FORMAT function to display the DATETIME values in the custom format:
SELECT id, DATE_FORMAT(datetime_column, '%d-%m-%Y %H:%i:%s') AS formatted_datetime FROM my_table;
This will retrieve the id and the DATETIME column in the 'DD-MM-YYYY HH:MM:SS' format.
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