Question

我正在尝试在mysql中重新创建在MS SQL中创建的东西。我有一点时间让语法正确。有谁知道对于以下内容，等效的mysql查询是什么：

 create table #tmp
(id int, Ran varchar(10), Result int, ref_id int)
insert #tmp values (1,  'Object1', 4.0,  1)
insert #tmp values (2,  'Object2', 100,  1)
insert #tmp values (3,  'Object1', 6.0,  2)
insert #tmp values (4,  'Object3', 89.0, 2)

select * from #tmp

Select t.ref_id
      ,TK =  max(case when t.Ran ='Object1' then t.[Result] end)
      ,CRP=  max(case when t.Ran ='Object2' then t.[Result] end)
      ,HPT=  max(case when t.Ran = 'Object3' then t.[Result] end)
      From #tmp t
group by t.ref_id

谢谢你看看！

Answer 1

这似乎并不困难：

create temporary table tmp (
    id int,
    Ran varchar(10),
    Result int,
    ref_id int
);

insert into tmp(id, Ran, Result, ref_id) values (1,  'Object1', 4.0,  1);
insert into tmp(id, Ran, Result, ref_id) values (2,  'Object2', 100,  1);
insert into tmp(id, Ran, Result, ref_id) values (3,  'Object1', 6.0,  2);
insert into tmp(id, Ran, Result, ref_id) values (4,  'Object3', 89.0, 2);

select * from tmp;

Select t.ref_id,
       max(case when t.Ran ='Object1' then t.Result end) as TK,
       max(case when t.Ran ='Object2' then t.Result end) as CRP,
       max(case when t.Ran = 'Object3' then t.Result end) as HPT
From tmp t
group by t.ref_id;

Here是一个非常接近的SQL Fiddle。

Answer 2

以上sql查询的MySQL等效查询：

create table #tmp
(id int, Ran varchar(10), Result int, ref_id int);
insert into #tmp values (1,  'Object1', 4.0,  1);
insert into #tmp values (2,  'Object2', 100,  1);
insert into #tmp values (3,  'Object1', 6.0,  2);
insert into #tmp values (4,  'Object3', 89.0, 2);

select * from #tmp;

Select t.ref_id
      ,TK =  max(case when t.Ran ='Object1' then t.Result end)
      ,CRP=  max(case when t.Ran ='Object2' then t.Result end)
      ,HPT=  max(case when t.Ran ='Object3' then t.Result end)
      from #tmp t
group by t.ref_id;

sql-server到mysql的翻译

2 个答案: