Oracle 中 LIMIT 子句的用法
LIMIT 子句用于限制 Oracle 查询返回的行数。它指定从查询结果集中检索的最大行数。
语法
<code>SELECT [列名] FROM [表名] [WHERE 条件] LIMIT [行数]</code>
参数
- 列名:要检索的列的名称。
- 表名:要查询的表的名称。
- 条件:可选。用于过滤查询结果的条件。
- 行数:要从结果集中检索的最大行数。
使用方法
要在 Oracle 中使用 LIMIT 子句,请将其添加到 SELECT 语句的末尾,如下所示:
<code>SELECT * FROM employees LIMIT 10;</code>
此查询将从 employees 表中检索前 10 行数据。
注意:
- LIMIT 子句必须出现在 ORDER BY 子句之后(如果有)。
- LIMIT 子句可以与 OFFSET 子句结合使用,以跳过指定数量的行,然后检索指定数量的行。
示例
以下示例展示了 LIMIT 子句的不同用法:
<code>-- 检索前 5 行数据 SELECT * FROM employees LIMIT 5; -- 检索从第 6 行开始的 5 行数据 SELECT * FROM employees ORDER BY employee_id LIMIT 5 OFFSET 5; -- 检索满足条件的前 5 行数据 SELECT * FROM employees WHERE salary > 50000 LIMIT 5;</code>
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