PostgreSQL DISTINCT 关键字。耳边二货
作者：互联网
在 PostgreSQL 中，DISTINCT 关键字与 SELECT 语句一起使用，用于去除重复记录，只获取唯一的记录。
我们平时在操作数据时，有可能出现一种情况，在一个表中有多个重复的记录，当提取这样的记录时，DISTINCT 关键字就显得特别有意义，它只获取唯一一次记录，而不是获取重复记录。
语法
用于去除重复记录的 DISTINCT 关键字的基本语法如下：
SELECT DISTINCT column1, column2,.....columnN
FROM table_name
WHERE [condition]
实例
创建 COMPANY 表（下载 COMPANY SQL 文件 ），数据内容如下：
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http://m.douguo.com/recipe/mip/2906302
http://m.douguo.com/recipe/amp/2906461
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http://m.douguo.com/recipe/amp/2908201
http://m.douguo.com/recipe/mip/2908201
标签：二货,PostgreSQL,DISTINCT,recipe,douguo,mip,amp,http,com 来源： https://www.cnblogs.com/guger/p/13431071.html