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mysql怎么查询某一字段不同值,在该字段中出现的次数

select s.`b`, count(*) c from `table` as s group by s.`b`

$total=0; //预设变量,用于存放累加结果 $sql="查询语句"; $sql=mysql_query($sql); while($as=mysql_fetch_array($sql)){ $total=$total+$as[0]; } 还有一种办法更好,假如你要累加的字段名为 price, 则: $sql="select sum(price) as total f...

select distinct 品牌 from 表名 或者 select 品牌 from 表名 group by 品牌

需要用group by中的having子句。 1、如test表中有如下数据: 2、现要查出dept出现2次以上的dept。可用如下语句: select dept from test group by dept having count(*) >2;3、查询结果:

SELECT num, COUNT(num) AS `count` FROM ( SELECT num FROM aaa UNION ALL SELECT num FROM bbb UNION ALL SELECT num FROM ccc ) AS Temp GROUP BY numORDER BY num

SELECT type, count(1) AS counts FROM material GROUP BY type。这是统计material表中type的重复次数

SELECT city_name, title, COUNT(*) FROM tuan_info GROUP BY city_name, title HAVING COUNT(*) >1

查看可用如下方法: 1、创建测试表,插入数据: create table product(id int,name varchar(10),totol int)insert into product values (1,'香蕉',100)insert into product values (2,'橘子',67)insert into product values (3,'葡萄',89)insert...

in(v1,v2..vn) ,符合v1,v2,,,vn才能被查出 IN关键字可以判断某个字段的值是否在指定的集合中。如果字段的值在集合中,则满足查询条件,该纪录将被查询出来。如果不在集合中,则不满足查询条件。其语法规则如下:[ NOT ] IN ( 元素1, 元素2, …, ...

myid是什么类型,是数值类型应这样写: select * from table where saleid=2376 and myid in (2,3,4,5,6) 如果myid是字符类型,应该这样写: select * from table where saleid=2376 and myid in ('2','3','4','5','6')

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