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14<b><i>db</i> <b>join</b></b>
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21<tt>
22<b><pre>db join
23	<i>db.cX</i>
24	<i>db.cY</i>
25	<i>db.cZ</i>
26	...
27</pre></b>
28<b>Description(db join)</b>
29<p>The <i>db</i> <b>join</b> command joins the specified cursors and returns a
30cursor handle that can be used to iterate through the joined {key data}
31pairs.  The returned cursor handle is bound to a Tcl command of the form
32<b>dbN.cX</b>, where X is an integer starting at 0 (for example,
33db0.c0 and db0.c1).  It is through this Tcl command that the script
34accesses the cursor methods.</p>
35<p>The returned join cursor has limited cursor functionality, and only the
36<i>dbc</i> <b>get</b> and <i>dbc</i> <b>close</b> commands will succeed.</p>
37<p>See <a href="../ref/am/join.html">Equality join</a> for more information on
38the underlying requirements for joining.</p>
39<p>In a transaction-protected environment, all the cursors listed must have
40been created within the same transaction.</p>
41<p>In the case of error, a Tcl error is thrown.</p>
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