<p>I'm maintaining some code that uses a *= operator in a query to a Sybase database and I can't find documentation on it.  Does anyone know what *= does?  I assume that it is some sort of a join.</p>

<pre><code>select * from a, b where a.id *= b.id</code></pre>

<p>I can't figure out how this is different from:</p>

<pre><code>select * from a, b where a.id = b.id</code></pre>

It means outer join, a simple = means inner join.
```
```
*= is LEFT JOIN and =* is RIGHT JOIN.
```
```
(or vice versa, I keep forgetting since I'm not using it any more, and Google isn't helpful when searching for *=)