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copied!<p>It seems this your latest query attempt:</p> <pre><code>SELECT a1.*, p.lifeSpan, a2.* FROM Zoo AS z INNER JOIN Plants AS p ON p.parent_id=z.id INNER JOIN Animal AS a1 ON (a1.id=z.predator) INNER JOIN Animal AS a2 ON (a2.id=z.prey)"; WHERE z.preyType=@carnivore </code></pre> <p>Discard the semicolon from inside the statement. Also discard the double quote. </p> <p>Just to simplify the SQL, exclude the WHERE clause for now. </p> <p>Then you should be in a better position to address the issue of parentheses which Access' db engine requires for multiple joins.</p> <pre><code>SELECT a1.*, p.lifeSpan, a2.* FROM ((Zoo AS z INNER JOIN Plants AS p ON p.parent_id=z.id) INNER JOIN Animal AS a1 ON a1.id=z.predator) INNER JOIN Animal AS a2 ON a2.id=z.prey </code></pre> <p>Notice I discarded those parentheses which enclosed the ON expressions. Simple ON expressions don't require them. If you had a compound expression for ON, then you would need parentheses like this:</p> <pre><code>ON (p.parent_id=z.id AND p.foo = z.bar) </code></pre> <p>The sample query I suggested looks correct to me. (If it works for you, add your WHERE clause back again.) However, I don't pay close attention to parentheses placement because I use Access' query designer to set up joins ... and it adds the parentheses the db engine requires. </p> <p>I urge you to do the same. If you're using an Access db from Dot.Net without having a copy of Access installed, you really should get a copy. Trying to use a database without that database's native development tools is an unreasonable challenge ... somewhat like trying to type while wearing mittens. </p>

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