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HomeDatabaseMysql TutorialWhy Does CONVERT_TZ Return NULL in MySQL, and How Can I Fix It?

Why Does CONVERT_TZ Return NULL in MySQL, and How Can I Fix It?

Understanding "CONVERT_TZ Returns NULL" Error

In MySQL, encountering a "CONVERT_TZ Returns NULL" error can be frustrating, especially when it looks Seems so straight forward. The reason may be that the MySQL time zone table has not yet been loaded into the database.

To load the time zone table, use the following command:

mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root -p mysql

In this command:

  • /usr/share/zoneinfo is the time zone information file path.
  • -u root -p allows you to connect to MySQL using the root user identity.
  • mysql is the name of the built-in database used to store MySQL-specific configuration data.

After executing this command, the time zone table will be loaded in the database. You can now run the CONVERT_TZ function again and it will correctly return the converted time.

Note: the mysql_tzinfo_to_sql command may vary depending on your system. Consult the MySQL documentation for details on specific commands.

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