Can MySQL Tables Now Have Multiple CURRENT_TIMESTAMP Columns?

Multiple TIMESTAMP Columns with CURRENT_TIMESTAMP: A Historical Restriction

In previous versions of MySQL, a limitation restricted tables to having only one TIMESTAMP column automatically initialized or updated to the current date and time using the CURRENT_TIMESTAMP clause. This constraint extended to both DEFAULT and ON UPDATE clauses.

Relaxed Restriction in MySQL 5.6.5

MySQL version 5.6.5 brought a significant change, lifting the historical restriction. With this release, any TIMESTAMP column can have any combination of DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP clauses.

Example:

The following table definition, which previously raised an error, is now valid starting from MySQL 5.6.5:

CREATE TABLE `foo` (
  `ProductID` INT(10) UNSIGNED NOT NULL,
  `AddedDate` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
  `UpdatedDate` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=INNODB;

Note: This change also applies to DATETIME column definitions, which now support the same clauses and combinations.

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