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Re: Difference between two SQL queries
Posted by: Guelphdad Lake
Date: July 18, 2011 05:55AM

Using comma join syntax you are able to leave off a join condition in the where clause. you will then have a cross join effect where every row from one table is returned for every row in the other table.

you can't leave off a join condition when you specifically use the INNER JOIN clause.

As for your second question you know how multiplication and division are performed before addition and subtraction in math questions?

Same things happen with joins, so you will get a join condition out of order if you join two tables with comma join syntax and mix in an INNER or OUTER join with the comma syntax.

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Guelphdad,
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Re: Difference between two SQL queries
July 18, 2011 05:55AM


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