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:
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:
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:
链接:https://www.learnfk.comhttps://www.learnfk.com/sqlite/sqlite-having-clause.html
来源:LearnFk无涯教程网
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