📅  最后修改于: 2020-11-11 04:49:57             🧑  作者: Mango
SQL ORDER BY子句用于根据一个或多个列以升序和降序对数据进行排序。
默认情况下,某些数据库以升序对查询结果进行排序。
SQL ORDER BY语法:
SELECT expressions
FROM tables
WHERE conditions
ORDER BY expression [ASC | DESC];
让我们看一个具有以下记录的CUSTOMERS表:
ID | NAME | AGE | ADDRESS | SALARY |
---|---|---|---|---|
1 | Himani gupta | 21 | Modinagar | 22000 |
2 | Shiva tiwari | 22 | Bhopal | 21000 |
3 | Ajeet bhargav | 45 | Meerut | 65000 |
4 | Ritesh yadav | 36 | Azamgarh | 26000 |
5 | Balwant singh | 45 | Varanasi | 36000 |
6 | Mahesh sharma | 26 | Mathura | 22000 |
此示例将按照NAME和SALARY的升序对结果进行排序。
SELECT * FROM CUSTOMERS
ORDER BY NAME, SALARY;
这将产生以下结果。
ID | NAME | AGE | ADDRESS | SALARY |
---|---|---|---|---|
3 | Ajeet bhargav | 45 | Meerut | 65000 |
5 | Balwant singh | 45 | Varanasi | 36000 |
1 | Himani gupta | 21 | Modinagar | 22000 |
6 | Mahesh sharma | 26 | Mathura | 22000 |
4 | Ritesh yadav | 36 | Azamgarh | 26000 |
2 | Shiva tiwari | 22 | Bhopal | 21000 |
这是一个按名称降序对结果进行排序的示例。
SELECT * FROM CUSTOMERS
ORDER BY NAME DESC;
这将产生以下结果。
ID | NAME | AGE | ADDRESS | SALARY |
---|---|---|---|---|
2 | Shiva tiwari | 22 | Bhopal | 21000 |
4 | Ritesh yadav | 36 | Azamgarh | 26000 |
6 | Mahesh sharma | 26 | Mathura | 22000 |
1 | Himani gupta | 21 | Modinagar | 22000 |
5 | Balwant singh | 45 | Varanasi | 36000 |
3 | Ajeet bhargav | 45 | Meerut | 65000 |