4 You can update existing rows using the UPDATE command. Suppose you
5 discover the temperature readings are all off by 2 degrees after
6 November 28. You can correct the data as follows:
8 SET temp_hi = temp_hi - 2, temp_lo = temp_lo - 2
9 WHERE date > '1994-11-28';
11 Look at the new state of the data:
12 SELECT * FROM weather;
14 city | temp_lo | temp_hi | prcp | date
15 ---------------+---------+---------+------+------------
16 San Francisco | 46 | 50 | 0.25 | 1994-11-27
17 San Francisco | 41 | 55 | 0 | 1994-11-29
18 Hayward | 35 | 52 | | 1994-11-29