ORDER BY

Description

Use the ORDER BY clause to order a resultset, such as that are returned from a SELECT statement. You can specify just a column or use any expression with functions. If you are using the GROUP BY clause, you can use grouping functions in ORDER BY. Ordering is done after grouping.

You can use multiple ordering expressions, separated by commas. Rows will be sorted by the first expression, then by the second expression if they have the same value for the first, and so on.

You can use the keywords ASC and DESC after each ordering expression to force that ordering to be ascending or descending, respectively. Ordering is ascending by default.

You can also use a single integer as the ordering expression. If you use an integer n, the results will be ordered by the nth column in the select expression.

When string values are compared, they are compared as if by the STRCMP function. STRCMP ignores trailing whitespace and may normalize characters and ignore case, depending on the collation in use.

MariaDB starting with 5.5.35

Starting from MariaDB 5.5.35 duplicated entries in the ORDER BY clause are removed. MySQL 5.6 also removes duplicated fields.

ORDER BY can also be used to order the activities of a DELETE or UPDATE statement (usually with the LIMIT clause).

MariaDB starting with 10.3.2

Until MariaDB 10.3.1, it was not possible to use ORDER BY (or LIMIT) in a multi-table UPDATE statement. This restriction was lifted in MariaDB 10.3.2.

Examples

CREATE TABLE seq (i INT, x VARCHAR(1));
INSERT INTO seq VALUES (1,'a'), (2,'b'), (3,'b'), (4,'f'), (5,'e');

SELECT * FROM seq ORDER BY i;
+------+------+
| i    | x    |
+------+------+
|    1 | a    |
|    2 | b    |
|    3 | b    |
|    4 | f    |
|    5 | e    |
+------+------+

SELECT * FROM seq ORDER BY i DESC;
+------+------+
| i    | x    |
+------+------+
|    5 | e    |
|    4 | f    |
|    3 | b    |
|    2 | b    |
|    1 | a    |
+------+------+

SELECT * FROM seq ORDER BY x,i;
+------+------+
| i    | x    |
+------+------+
|    1 | a    |
|    2 | b    |
|    3 | b    |
|    5 | e    |
|    4 | f    |
+------+------+

ORDER BY in an UPDATE statement, in conjunction with LIMIT:

UPDATE seq SET x='z' WHERE x='b' ORDER BY i DESC LIMIT 1;

SELECT * FROM seq;
+------+------+
| i    | x    |
+------+------+
|    1 | a    |
|    2 | b    |
|    3 | z    |
|    4 | f    |
|    5 | e    |
+------+------+

From MariaDB 10.3.2, ORDER BY can be used in a multi-table update:

CREATE TABLE warehouse (product_id INT, qty INT);
INSERT INTO warehouse VALUES (1,100),(2,100),(3,100),(4,100);

CREATE TABLE store (product_id INT, qty INT);
INSERT INTO store VALUES (1,5),(2,5),(3,5),(4,5);

UPDATE warehouse,store SET warehouse.qty = warehouse.qty-2, store.qty = store.qty+2 
  WHERE (warehouse.product_id = store.product_id AND store.product_id  >= 1) 
    ORDER BY store.product_id DESC LIMIT 2;

SELECT * FROM warehouse;
+------------+------+
| product_id | qty  |
+------------+------+
|          1 |  100 |
|          2 |  100 |
|          3 |   98 |
|          4 |   98 |
+------------+------+

SELECT * FROM store;
+------------+------+
| product_id | qty  |
+------------+------+
|          1 |    5 |
|          2 |    5 |
|          3 |    7 |
|          4 |    7 |
+------------+------+

See Also

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