1<!--$Id: db_join.so,v 11.22 2002/08/18 21:17:26 bostic Exp $--> 2<!--$Id: m4.tcl,v 11.28 2004/12/16 19:13:05 bostic Exp $--> 3<!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> 4<!--See the file LICENSE for redistribution information.--> 5<html> 6<head> 7<title>Berkeley DB: db join</title> 8<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> 9<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> 10</head> 11<body bgcolor=white> 12<table width="100%"><tr valign=top> 13<td> 14<b><i>db</i> <b>join</b></b> 15</td> 16<td align=right> 17<a href="../api_tcl/api_tcl.html"><img src="../images/api.gif" alt="API"></a> 18<a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a></td> 19</tr></table> 20<hr size=1 noshade> 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> 42</tt> 43<table width="100%"><tr><td><br></td><td align=right> 44<a href="../api_tcl/api_tcl.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> 45</td></tr></table> 46<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 47</body> 48</html> 49