海友我对数据库查询有疑问 [英] Hai Friends I Have A Question On Database Query

问题描述

我有三张桌子

喜欢



桌子

 tlid mbno名称性别
 tl1 123是m 

table1

 id tlid rfid 
 1 tl1 12 
 2 tl1 
 3 tl1 

table2

 rfid type abc xyz tlid 
 12 one a .. x .. tl1 

i想要显示详细信息，例如



如何为此写一个查询你可以告诉我依赖于mbno

 tlid id name性别类型abc xyz 
 tl1 1是m one a one .. x .. 
 tl1 2是m 
 tl1 3是m 

i不想这样展示

 tlid id name性别类型abc xyz 
 tl1 1是m one a .. x .. 
 tl1 1 yes m 
 tl1 2 yes m 
 tl1 3是m 

解决方案

Tr y：

  SELECT  a.tlid，a.id，b.name，b.gender，c 。 type ，c.abc，c.xyz 
  FROM  table1 a 
 < span class =code-keyword> JOIN  [ table ] b  ON  a.tlid = b.tlid 
  LEFT   JOIN  table2 c  ON  a.rfid = c.rfid 

SELECT table.tlid，

table1.id，
table.NAME，

table.gender，

table2.TYPE，

table2.abc，

table2.xyz

FROM table

LEFT JOIN table1 ON（table.tlid = table1.tlid）

LEFT JOIN table2 ON（ table2.rfid = table1.rfid

AND table.tlid = table2.tlid

）

i have three tables
like

table

tlid mbno name gender 
tl1   123   yes      m 

table1

id   tlid	 rfid
1     tl1	 12	
2     tl1       
3     tl1

table2

rfid   type  abc  xyz tlid
12     one    a..   x..   tl1

i want to show the details like

how to write a query for this can you please tell me depend on mbno

tlid  id  name gender type abc xyz
tl1    1    yes      m     one  a..  x..
tl1    2    yes      m 
tl1    3    yes      m 

i don't wanna show like this

tlid  id  name gender type abc xyz
tl1    1    yes      m     one  a..  x..
tl1    1    yes      m
tl1    2    yes      m 
tl1    3    yes      m

解决方案

Try:

SELECT a.tlid, a.id, b.name, b.gender, c.type, c.abc, c.xyz
FROM table1 a
JOIN [table] b ON a.tlid = b.tlid
LEFT JOIN table2 c ON a.rfid = c.rfid

SELECT table.tlid ,
table1.id ,
table.NAME ,
table.gender ,
table2.TYPE ,
table2.abc ,
table2.xyz
FROM table
LEFT JOIN table1 ON ( table.tlid = table1.tlid )
LEFT JOIN table2 ON ( table2.rfid = table1.rfid
AND table.tlid = table2.tlid
)

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