无涯教程-SQLite - Having语句

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SQLite HAVING子句用于指定条件,该条件用于过滤哪些组结果出现在最终结果中。 WHERE子句在所选列上放置条件,而HAVING子句在GROUP BY子句创建的组上放置条件。

HAVING子句在SELECT查询中的位置:

SELECT
FROM
WHERE
GROUP BY
HAVING
ORDER BY

语法:

SELECT column1, column2
FROM table1, table2
WHERE [ conditions ]
GROUP BY column1, column2
HAVING [ conditions ]
ORDER BY column1, column2

示例:

让无涯教程以一个示例来演示HAVING子句。无涯教程有一个名为" STUDENT"的表,其中包含以下数据:

Sqlite Having clause 1

示例1:

显示名称计数少于2的所有记录:

SELECT * FROM STUDENT GROUP BY NAME HAVING COUNT(NAME) < 2; 

输出:

Sqlite Having clause 2

示例2:

显示名称计数大于2的所有记录:

SELECT * FROM STUDENT GROUP BY NAME HAVING COUNT(NAME) > 2;

输出:

Sqlite Having clause 3

参考链接

www.learnfk.com/sqlite/sqli…