Convert date to datetime or timestamp using alter table in mysql
I have a table in mysql with DATE column, now I need to convert these values to DATETIME or TIMESTAMP.
I wonder what will happen with data when I'll do:
ALTER TABLE sample MODIFY sample_date DATETIME
or
ALTER TABLE sample MODIFY sample_date TIMESTAMP
It's pretty straight forward to convert from one type to another using the ALTER TABLE command:
ALTER TABLE table_name CHANGE old_date new_timestamp TIMESTAMP This process may take a while to complete if you have a lot of data and a large number of indexes.
I'm not sure why you'd want to switch these to the TIMESTAMP type as that has a much more limited range than DATETIME. The differences are documented and important to know.
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