You may have noticed in the preceding examples that the result
rows are displayed in no particular order. It's often easier
to examine query output when the rows are sorted in some
meaningful way. To sort a result, use an ORDER
BY
clause.
Here are animal birthdays, sorted by date:
mysql> SELECT name, birth FROM pet ORDER BY birth;
+----------+------------+
| name | birth |
+----------+------------+
| Buffy | 1989-05-13 |
| Bowser | 1989-08-31 |
| Fang | 1990-08-27 |
| Fluffy | 1993-02-04 |
| Claws | 1994-03-17 |
| Slim | 1996-04-29 |
| Whistler | 1997-12-09 |
| Chirpy | 1998-09-11 |
| Puffball | 1999-03-30 |
+----------+------------+
On character type columns, sorting — like all other
comparison operations — is normally performed in a
case-insensitive fashion. This means that the order is
undefined for columns that are identical except for their
case. You can force a case-sensitive sort for a column by
using BINARY
like so: ORDER BY
BINARY col_name
.
The default sort order is ascending, with smallest values
first. To sort in reverse (descending) order, add the
DESC
keyword to the name of the column you
are sorting by:
mysql> SELECT name, birth FROM pet ORDER BY birth DESC;
+----------+------------+
| name | birth |
+----------+------------+
| Puffball | 1999-03-30 |
| Chirpy | 1998-09-11 |
| Whistler | 1997-12-09 |
| Slim | 1996-04-29 |
| Claws | 1994-03-17 |
| Fluffy | 1993-02-04 |
| Fang | 1990-08-27 |
| Bowser | 1989-08-31 |
| Buffy | 1989-05-13 |
+----------+------------+
You can sort on multiple columns, and you can sort different
columns in different directions. For example, to sort by type
of animal in ascending order, then by birth date within animal
type in descending order (youngest animals first), use the
following query:
mysql> SELECT name, species, birth FROM pet
-> ORDER BY species, birth DESC;
+----------+---------+------------+
| name | species | birth |
+----------+---------+------------+
| Chirpy | bird | 1998-09-11 |
| Whistler | bird | 1997-12-09 |
| Claws | cat | 1994-03-17 |
| Fluffy | cat | 1993-02-04 |
| Fang | dog | 1990-08-27 |
| Bowser | dog | 1989-08-31 |
| Buffy | dog | 1989-05-13 |
| Puffball | hamster | 1999-03-30 |
| Slim | snake | 1996-04-29 |
+----------+---------+------------+
Note that the DESC
keyword applies only to
the column name immediately preceding it
(birth
); it does not affect the
species
column sort order.