本文將爲您介紹如何對數據隨機取出數據的前 N 條數據。
示例數據
目前的數據，如下表所示：
| empno | ename | job | sal |
|---|---|---|---|
| 7369 | SMITH | CLERK | 800.0 |
| 7876 | SMITH | CLERK | 1100.0 |
| 7900 | JAMES | CLERK | 950.0 |
| 7934 | MILLER | CLERK | 1300.0 |
| 7499 | ALLEN | SALESMAN | 1600.0 |
| 7654 | MARTIN | SALESMAN | 1250.0 |
| 7844 | TURNER | SALESMAN | 1500.0 |
| 7521 | WARD | SALESMAN | 1250.0 |
實現方法
通過order by rand()來實現隨機抽取效果。
SELECT empno
, ename
, sal
, job
FROM emp
order by rand() limit 3