What Is TIMESTAMP

Q

What Is TIMESTAMP? - MySQL FAQs - Introduction to SQL Date and Time Handling

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A

A TIMESTAMP data type allows you to record a date and time like DATETIME data type. But it has some interesting features when used on a table column:

The first TIMESTAMP column in a table will be assigned with the current date and time, if it is not listed in an INSERT statement.
The first TIMESTAMP column in a table will be assigned with the current date and time, if it is not listed in an UPDATE statement.
If a TIMESTAMP column is assigned with NULL, the current date and time will be persisted to this column.
You can turn off the default current date and time on INSERT by defining the column with "DEFAULT 0".

The tutorial exercise below provides you 2 equivalent ways to create a TIMESTAMP column:

CREATE TABLE links (lastDate TIMESTAMP);

CREATE TABLE links (lastDate TIMESTAMP 
   DEFAULT CURRENT_TIMESTAMP
   ON UPDATE CURRENT_TIMESTAMP);

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