Can I Have Both Created and LastUpdated Timestamp Columns in MySQL 4.0?-Mysql Tutorial-php.cn

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Can I Have Both Created and LastUpdated Timestamp Columns in MySQL 4.0?

Susan Sarandon

Nov 13, 2024 am 02:44 AM

Can I Have Both Created and LastUpdated Timestamp Columns in MySQL 4.0?

Having Both Created and Last Updated Timestamp Columns in MySQL 4.0

Issue:

When creating a MySQL 4.0 table with both Created and LastUpdated TIMESTAMP columns, the following error is encountered:

ERROR 1293 (HY000): Incorrect table definition; there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT or ON UPDATE clause.

Question:

Is it possible to have both Created and LastUpdated timestamp columns in MySQL 4.0?

Answer:

MySQL 5.5 and Earlier:

No. According to the MySQL 5.5 documentation, only one TIMESTAMP column per table can have the current timestamp as either the default value for initialization or the auto-update value.

MySQL 5.6.5 and Later:

Yes. In MySQL 5.6.5, the restriction on having only one automatically initialized or updated TIMESTAMP column was lifted. Now, any TIMESTAMP column can have a combination of DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP clauses.

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