Question

I have a fairly conventional set of order entry tables divided by:

Orders
OrdersRows
OrdersRowsOptions

The record in OrderRowOptions is not created unless needed. When I create a set of joins like

select * from orders o 
  inner join OrdersRows r on r.idOrder = o.idOrder 
  inner join ordersrowsoptions ro on ro.idOrderRow = r.idOrderRow
where  r.idProduct = [foo]

My full resultset is blank if no ordersrowsoptions records exist for the given product.

what’s the correct syntax to return records even if no records exist at one of the join clauses?

thx

Answer 1

select * from orders o  
  inner join OrdersRows r on r.idOrder = o.idOrder  
  left join ordersrowsoptions ro on ro.idOrderRow = r.idOrderRow 
where  r.idProduct = [foo] 

Of course you should not use select * in any query but especially never when doing a join. The repeated fields are just wasting server and network resources.

Since you seem unfamiliar with left joins, you probably also need to understand the concepts in this:
http://wiki.lessthandot.com/index.php/WHERE_conditions_on_a_LEFT_JOIN