Deletions are performed using the DELETE
command.
Say that you are no longer interested in the weather of Hayward.
You can do the following to delete those rows from the table:
DELETE FROM weather WHERE city = 'Hayward'; |
All weather records belonging to Hayward are removed.
city | temp_lo | temp_hi | prcp | date
---------------+---------+---------+------+------------
San Francisco | 46 | 50 | 0.25 | 1994-11-27
San Francisco | 41 | 55 | 0 | 1994-11-29
(2 rows) |
One should be wary of queries of the form
Without a qualification,
DELETE will
remove
all rows from the given table, leaving it
empty. The system will not request confirmation before
doing this!