join question

  • Thread starter Thread starter Gary B
  • Start date Start date
G

Gary B

if i have some tables that have inner joins amongst themselves where one
join per table is enough to acomplish my desired result...

BUT,

these tables also have other keys in common.

Is it advantageous to declare all relationships in the FROM clause in order
to maximize the most optimized(fastest) query?
 
Telling the query engine to join on more fields just makes it do more work.
If your current single join solves the problem and you have indexes defined
on those fields, then don't tamper with success. Saying that you have other
keys in common leads me to believe that you might have a fundamental table
design problem. You should normally have a relationship only between the
Primary Key of one table and the Foreign Key of the related table. Any
other "matching" information is unnecessary duplication of values.

--
John Viescas, author
"Microsoft Office Access 2003 Inside Out"
"Running Microsoft Access 2000"
"SQL Queries for Mere Mortals"
http://www.viescas.com/
(Microsoft Access MVP since 1993)
 
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