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orAClE里怎么统计某个字段出现的重复次数

select AREA_ID,sum(NVL(decode(RANGE_,100,count_),0)) as COUNT_100,sum(NVL(decode(RANGE_,200,count_),0)) as COUNT_200,sum(NVL(decode(RANGE_,300,count_),0)) as COUNT_300 from test1 group by area_id

对于你的要求,应该是这样select count(id) from 表 where id = '1'但是如果你需要查询表id字段中所有数据出现的次数,那需要进行分组查询:select id,count(id) as 出现次数 from 表 group by id

用count既可以查出重复次数.例:tabletest 表,有A、B、C3个字段.要查找字段B的重复次数select count(A), B from tabletest group by B;即可查出B字段下每个值的重复次数,如果要查有重复数据的总和select count(A), B from tabletest group by B having count(A)>1;

declare @tt Table (name varchar(100)) insert into @tt values ('张三') insert into @tt values ('李四,张三') insert into @tt values ('王五 赵六') insert into @tt values ('赵六') insert into @tt values ('李四') insert into @tt values ('王五,赵

以某个字段重复为例select column,count(*) from table group by column having count(*)>1查出来的结果就代表某个字段有重复的

select testid,count(1) from testtable group by testid having count(1)>1 count(1)就是重复在数量 如何查询重复的数据 select 字段1,字段2,count(*) from 表名 group by 字段1,字段2 having count(*) > 1 PS:将上面的>号改为=号就可以查询出没有重

方法一:可以通过group by 进行分组.sql:select username,count(username) from tablename grop by username; 解释:以上sql就是通过分组函数读取出tablename表中username的值和每个不同值的统计个数.方法二:可以通过distinct函数 进行去重查询.sql:select distinct username from tablename 解释:本sql就是查询出所有的tablename表中的username值(不重复).

用count既可以查出重复次数.例:tabletest 表,有a、b、c3个字段.要查找字段b的重复次数select count(a), b from tabletest group by b;即可查出b字段下每个值的重复次数,如果要查有重复数据的总和select count(a), b from tabletest group by b having count(a)>1;

对于你的要求,应该是这样select count(id) from 表 where id = '1'但是如果你需要查询表id字段中所有数据出现的次数,那需要进行分组查询:select id,count(id) as 出现次数 from 表 group by id

可以通过insert into …… as select 语句来进行实现.sql:insert into tablename(newname) as select oldname from tablename where 条件语句.备注:以上语句中插入的字段顺序必须要和查询的语句的顺序保持一致,否则会报错,如果有条件语句的话,可以增加 where条件.

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