SQLite的HAVING子句用于指定该滤波器组的结果出现在最终的结果的条件。在WHERE所选列条款场所的条件,而由GROUP BY子句创建组HAVING子句场所的条件。
在SELECT查询HAVING子句的位置:
SELECT
FROM
WHERE
GROUP BY
HAVING
ORDER BY
句法:
SELECT column1,column2
FROM table1,table2
WHERE [ conditions ]
GROUP BY column1,column2
HAVING [ conditions ]
ORDER BY column1,column2
例:
让我们举个例子来说明HAVING子句。我们有一个表名为“学生”,具有下列数据:
例1:
显示所有记录的名字计数小于2:
SELECT * FROM STUDENT GROUP BY NAME HAVING COUNT(NAME) < 2;
输出:
例2:
显示所有记录的名字计数大于2:
SELECT * FROM STUDENT GROUP BY NAME HAVING COUNT(NAME) > 2;
输出:
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