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Re: Why is this a cross join?

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>
> In some way, every join is a cross join, with the results filtered according to the specificity of the join conditions. In this case:
>
> inner join model_configurations mc on left(crm.customer_class, 6) = left(mc.sap_code,6)
>
> "customer_class" sounds like a fairly generic sort of field, so you'd expect many matches. Truncating the fields is likely to make this even less specific, returning more results.
>

I guess I am not explaining it properly..

Say I created new columns on both tables called "first_6" and
populated them with the substrings.  If I did a inner join or a left
join on those fields would I still get a cross join?

inner join model_configurations mc on mc.first_6 = crm.first_6


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