The TIMESTAMP data type is a column definition that contains the date and time as one field. A TIMESTAMP is frequently used for audit records to establish when critical data has been changed. It is stored internally as ‘CCYY-MM-DD HH.MM.SS.MMMMMM’ (up to 26 in length). A timestamp column must have a valid date and time and can not be blank. If the column is defined as allowing NULLs, then NULL should be used for a missing timestamp.

Example:    COL1 TIMESTAMP

Sample value is: ’2056-02-20 17:39.45′

Notice that the keyword, TIMESTAMP, is a complete definition of the data type and has no value defined in parentheses. See Sample Data Type Values.

TIMESTAMP WITHOUT TIME ZONE is the same as TIMESTAMP. In this course, we use TIMESTAMP.

TIMESTAMP WITH TIME ZONE is the same as TIME WITH TIME ZONE, it’s just a timestamp with a time zone.