如何从oracle sql中仅选择1行? [英] How to select only 1 row from oracle sql?

问题描述

我想使用oracle语法从表DUAL中仅选择1行.例如，我要执行以下查询:

I want to use oracle syntax to select only 1 row from table DUAL. For example, I want to execute this query:

SELECT user 
  FROM DUAL

...它将有40条记录.但是我只需要一个记录. ...而且，我想在没有WHERE子句的情况下实现它.

...and it'd have, like, 40 records. But I need only one record. ...AND, I want to make it happen without a WHERE clause.

我在table_name字段中需要一些东西，例如:

I need something in the table_name field such as:

SELECT FirstRow(user) 
  FROM DUAL

推荐答案

您使用ROWNUM.

即.

SELECT user FROM Dual WHERE ROWNUM = 1

http://docs.oracle.com/cd/B19306_01/server.102 /b14200/pseudocolumns009.htm

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