Adding a new column with the current time as a default value

Question

I am looking for the syntax to add a column to a MySQL table with the current time as a default value.

Answer 1

Even so many persons have provided solution but this is just to add more information-

If you just want to insert current timestamp at the time of row insertion-

    ALTER TABLE mytable ADD mytimestampcol TIMESTAMP DEFAULT CURRENT_TIMESTAMP;

If you also want that this column should update if any update this row then use this-

    ALTER TABLE mytable ADD mytimestampcol TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP;

Answer 2

IMPORTANT EDIT: It is now possible to achieve this with DATETIME fields since MySQL 5.6.5, take a look at the other post below...

It is now possible to achieve this with DATETIME fields since MySQL 5.6.5
But you can do it with TIMESTAMP:

 create table test (str varchar(32), ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP)