Question

表1

name  closedid
rere    4
trtr    5
ewew    6

和表2

name  openedid 
rere    6
trtr    7
ytyt    8 
uyuy    5

和

table-3
name  assign 
rere    6
ytyt    8 
uyuy    5
rtyy    9

和表4

name  unassign 
rere    6
trtr    7
errt    5
hdtg    9

我想要这样的最终输出：

name closedid  opened assign unassign
rere    4         6     6      6
trtr    5         7     null   7
ytyt    null      8     8      null
uyuy    null      5     5      null
ewew    6         null  null   null
rtyy    null      null  9      null
errt    null      null  null   5
hdtg    null      null  null   9

Answer 1

我想，这就是你要找的东西：

  SELECT coalesce(t1.NAME, t2.NAME, t3.NAME, t4.NAME) NAME
    ,t1.closedid
    ,t2.openedid
    ,t3.assign
    ,t4.unassign
FROM [table-1] t1
FULL OUTER JOIN [table-2] t2 ON t1.NAME = t2.NAME
FULL OUTER JOIN [table-3] t3 ON isnull(t1.NAME, t2.NAME) = t3.NAME
FULL OUTER JOIN [table-4] t4 ON coalesce(t1.NAME, t2.NAME, t3.NAME) = t4.NAME

Answer 2

我会抓住所有不同的名字，然后对该列表进行左连接，这样可以更容易理解发生了什么。

;WITH cte(name)
AS (
    SELECT name FROM table1
    UNION
    SELECT name FROM table2
    UNION
    SELECT name FROM table3
    UNION
    SELECT name FROM table4
)
SELECT
  cte.name,
  table1.closedid,
  table2.openid,
  table3.assign,
  table4.unassign
FROM
  cte
  LEFT JOIN table1 ON cte.name = table1.name
  LEFT JOIN table2 on cte.name = table2.name
  LEFT JOIN table3 on cte.name = table3.name
  LEFT JOIN table4 on cte.name = table4.name

SQLFiddle

Answer 3

使用UNION获取明确的名单
使用LEFT JOIN检索您的数据

示例：

SELECT list.name, t1.assigned, t2.unsassigned, t3.closed, t4.open
FROM 
   (select name from table1
    union select name from table2
    union select name from table3
    union select name from table4
   ) list
LEFT JOIN table1 t1 ON (list.name = t1.name)
LEFT JOIN table2 t2 ON (list.name = t2.name)
LEFT JOIN table3 t3 ON (list.name = t3.name)
LEFT JOIN table4 t4 ON (list.name = t4.name)

Answer 4

select coalesce(t1.name,t2.name,t3.name,t4.name) name,  t1.closeid, t2.openid, t3.assign, t4.unassign
from table-1 t1
full outer join table-2 t2 on t1.name = t2.name
full outer join table-3 t3 on t2.name = t3.name
full outer join table-4 t4 on t3.name = t4.name

Answer 5

select
n.name, t1.closedid, t2.openedid, t3.assign, t4.unassign
from 
(select name from [table-1]
union
select name from [table-2]
union
select name from [table-3]
union
select name from [table-4]
) as n 
left join [table-1] t1 on n.name  = t1.name
left join [table-2] t2 on n.name = t2.name
left join [table-3] t3 on n.name = t3.name
left join [table-4] t4 on n.name = t4.name

如何将4个表连接到单个表中？

5 个答案: