mysql query to show everything that does not join :) [closed]

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 11 years ago. 开发者_如何学Go

Imagine two tables that both have a common ID field that joins two tables together.

Lets call them Table1 and Table2.

Table1 joins Table2 on the field ID.

How do I get all results on Table2 that has an ID that

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guessing you need one of these

SELECT * FROM table1 JOIN LEFT table2 ON table1.id=table2.id WHERE table2.id IS NULL

or

SELECT * FROM table1 JOIN LEFT table2 ON table1.id=table2.id WHERE table2.id IS NOT NULL

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select * from Table2 where ID not in (select ID from Table1)

or

select * from (select * from Table1 right join Table2 on Table1.ID = Table2.ID) where foo is NULL

in which foo must be a column from Table1 that does not exist in Table2 and is never null in Table1.

EDIT: whoops, you can actually use ID as foo, as long as you qualify it with the table names:

select * from Table1.ID right join Table2.ID where Table1.ID is NULL

As explained here: http://www.codeproject.com/KB/database/Visual_SQL_Joins/Visual_SQL_JOINS_orig.jpg

Also interesting: http://www.codinghorror.com/blog/2007/10/a-visual-explanation-of-sql-joins.html

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http://www.wellho.net/mouth/158_MySQL-LEFT-JOIN-and-RIGHT-JOIN-INNER-JOIN-and-OUTER-JOIN.html is that you want?!

mysql> select name, phone, selling 

from Table2 join Table1 

on Table2.pid = Table1.pid;

Or you want:

mysql> select *

from Table2 

where Table2.pid is not null;