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<h1><i>db</i> <b>join</b></h1>
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<h3><pre>db join
<i>db.cX</i>
<i>db.cY</i>
<i>db.cZ</i>
...
</pre></h3>
<h1>Description</h1>
<p>The <i>db</i> <b>join</b> command joins the specified cursors and returns a
cursor handle that can be used to iterate through the joined {key data}
pairs. The returned cursor handle is bound to a Tcl command of the form
<b>dbN.cX</b>, where X is an integer starting at 0 (e.g., db0.c0 and
db0.c1). It is through this Tcl command that the script accesses the
cursor methods.
<p>The returned join cursor has limited cursor functionality and only the
<i>dbc</i> <b>get</b> and <i>dbc</i> <b>close</b> commands will succeed.
<p>See <a href="../ref/am/join.html">Logical join</a> for more information on
the underlying requirements for joining.
<p>In a transaction protected environment, all of the cursors listed must
have been created within the same transaction.
<p>In the case of error, a Tcl error is thrown.
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