Re: Under what circumstances should one use a non-equijoin?

As a hypothetical example, how about:

    where stock.next_delivery_date > order_line.order_date + 7     and stock.stock_code = order_line.stock_code

Although the stock_code equi-join is pk/fk, the date predicate is non-key and is a non-equijoin, but does not necessarily suggest a bad design.

-- 
Regards

Jonathan Lewis
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<dananrg_at_yahoo.com> wrote in message 
news:1149196317.088654.221960_at_i39g2000cwa.googlegroups.com...


> It is good or bad practice to perform non-equijoins - e.g. to do table

> joins where there is no formal foreign key to relate two tables.

>

> Under what circumstances is it necessary or desirable to perform

> non-equijoins? Can someone give a few examples?

>

> If I have to perform a non-equijoins, does this mean I'm using a poorly

> designed RDBMS?

>