要count distinct兩個field name如何用 SELECT count(distinct CUSTMER,CODE) FROM A 好像不能用

Use subquery if it supports, e.g. select count(*) from (select distinct CUSTMER, CODE) from A)

引言: Use subquery if it supports, e.g. select count(*) from (select distinct CUSTMER, CODE) from A)

不行...,是用DEPHLI,EXPLORER,是否還有別的方法

If CUSTMER and CODE are string fields, try this:    

select count(*) from A where CUSTMER   ':'   CODE in (
    select distinct CUSTMER   ':'   CODE from A)

都轉成字串相加後, 再去Distinct 例如: SQL Server SELECT count(distinct CUSTMER ' ' CODE) FROM A InterBase or Oracle SELECT count(distinct CUSTMER||' '||CODE) FROM A 我不是高手, 高手是正在銀幕前微笑的人.

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我不是高手, 高手是正在銀幕前微笑的人.

您好!    請問您所指的要count distinct兩個field name是指如下哪一種要求: 1. 同時Distinct Field1和Field2, 同時符合條件的再Count //Select Count(*) From (Select Distinct Field1, Field2 From Table) 2. 先Distinct Field1, 再Distinct Field2, 再加兩個結果Count //Select Count(*) From (Select Distinct Field1 From Table Union Select Field2 From Table) 參考看看! ===================== 努力,相信會獲得美麗! 忻晟

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忻晟