Coditional join of query using PostgreSQL

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<div dir="ltr">Hi, <br />I'm new to postgresql and couldn't find answer to this situation anywhere. <br />I asked this here: <br /><a href="http://stackoverflow.com/questions/43984208/coditional-join-of-query-using-postgresql" target="_top" rel="nofollow">http://stackoverflow.com/questions/43984208/coditional-join-of-query-using-postgresql</a><br /><br />I hope there is a better solution rather than creating two separated functions :(</div>
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