postgresql如何查询重复计数及去重查询
作者：cuisidong1997
这篇文章主要介绍了postgresql如何查询重复计数及去重查询问题,具有很好的参考价值,希望对大家有所帮助,如有错误或未考虑完全的地方,望不吝赐教
postgresql查询重复计数及去重查询
1、重复计数
SELECT id, name, email, count(*) over (partition by email) cnt FROM people
2、字段相同值计数排序
SELECT id, name, email, row_number() over (PARTITION BY email ORDER BY id DESC) AS row_num FROM people
3、去重查询
3.1、
select distinct on (a) a,b,c from t_distinct;
返回a唯一的任意行
3.2、
select distinct a,b,c from t_distinct;
返回 a,b,c 唯一值。
postgresql对字段中的重复值计数
1、重复计数
SELECT 号码,属性,count(*) over (PARTITION BY 号码) AS “row_num” from (select 号码,‘需更换终端用户' as 属性 from “市场部0330需更换终端用户明细” union SELECT 号码,‘需更换卡槽' as 属性 FROM “市场部0330需升级终端版本打开VoLTE开关更换卡槽”) as ss
2、字段相同值计数排序
SELECT 号码,属性,row_number() over (PARTITION BY 号码 ORDER BY 号码 DESC) AS “row_num” from (select 号码,‘需更换终端用户' as 属性 from “市场部0330需更换终端用户明细” union SELECT 号码,‘需更换卡槽' as 属性 FROM “市场部0330需升级终端版本打开VoLTE开关更换卡槽”) as ss
总结
以上为个人经验，希望能给大家一个参考，也希望大家多多支持脚本之家。