Nested RIGHT JOINs ?

[Jean-Louis Leroy]

Hello,

I have been assigned to fix a bug in an Access application. I have microscopic experience with Access though. When looking at the SQL version of a query, I see constructs like this:

SELECT ... FROM X AS X1
RIGHT JOIN (Y AS Y1
RIGHT JOIN Z ON Y1.yyy = Z.zzz)
ON X1.xxx = Y1.yyy
WHERE ...

I'm a bit puzzled by the nested RIGHT JOIN syntax. I have tried to find a comprehensive reference for MS Access SQL on the web, without success. My best guess is that it's functionally the same as (but maybe more optimizer-friendly than):

SELECT ... FROM X AS X1
RIGHT JOIN Y AS Y1 ON X1.xxx = Y1.yyy
RIGHT JOIN Z ON Y1.yyy = Z.zzz

Can someone fill me in ?

Thanks,
Jean-Louis

 

[Thomko]

Hello Jean-Louis,

welcome to AWF.

Here some links on ACESS/JET SQL
Fundamental Microsoft Jet SQL for Access 2000
Intermediate Microsoft Jet SQL for Access 2000
Advanced Microsoft Jet SQL for Access 2000

And a page about JOINs
LEFT JOIN, RIGHT JOIN Operations

You might want to learn a bit about the ACCESS query designer, as it gives a very nice graphical representation of the query structure.

HTH
Thomas