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diff --git a/db/docs/ref/bdb_index/views.html b/db/docs/ref/bdb_index/views.html deleted file mode 100644 index 5fdbed2d8..000000000 --- a/db/docs/ref/bdb_index/views.html +++ /dev/null @@ -1,144 +0,0 @@ -<!--$Id: views.html,v 1.1 2003/12/15 21:43:45 jbj Exp $--> -<!--Copyright 1997-2003 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<!--See the file LICENSE for redistribution information.--> -<html> -<head> -<title>Berkeley DB Reference Guide: Creating indexed collections</title> -<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> -<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> -</head> -<body bgcolor=white> -<a name="2"><!--meow--></a> -<table width="100%"><tr valign=top> -<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Java API Tutorial - Index</dl></h3></td> -<td align=right><a href="../bdb_index/foreign.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../bdb_index/read.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p> -<h3 align=center>Creating indexed collections</h3> -<p>In the prior Basic example, bindings and Java collections were created -for accessing stores via their primary keys. In this example, bindings and -collections are added for accessing the same stores via their index keys. As -in the prior example, serial bindings and the Java -<a href="http://java.sun.com/j2se/1.3/docs/api/java/util/Map.html">Map</a> - class are used.</p> -<p>When a map is created from a -<a href="../../java/com/sleepycat/bdb/DataIndex.html">DataIndex</a> -or a -<a href="../../java/com/sleepycat/bdb/ForeignKeyIndex.html">ForeignKeyIndex</a> -, the keys of the map -will be the index keys. However, the values of the map will be the values of -the store associated with the index. This is how index keys can be used to -access the values in a store.</p> -<p>For example, the Supplier's City field is an index key that can be used -to access the Supplier store. When a map is created using the -<b>supplierByCityIndex</b>, the key to the map will be the City field, a -<a href="http://java.sun.com/j2se/1.3/docs/api/java/lang/String.html">String</a> - object. When -<a href="http://java.sun.com/j2se/1.3/docs/api/java/util/Map.html#get">Map.get</a> - is called passing the City as the key parameter, a <b>SupplierValue</b> -object will be returned.</p> -<hr size=1 noshade> -<p>The <b>SampleViews</b> class is extended to create an index key -binding for the Supplier's City field and three Java maps based on the three -indices created in the prior section.</p> -<blockquote><pre> -import com.sleepycat.bdb.bind.DataBinding; -import com.sleepycat.bdb.bind.serial.SerialBinding; -import com.sleepycat.bdb.collection.StoredEntrySet; -import com.sleepycat.bdb.collection.StoredMap; -<p> -public class SampleViews -{ - ... -<b> private StoredMap supplierByCityMap; - private StoredMap shipmentByPartMap; - private StoredMap shipmentBySupplierMap; -</b><p> - public SampleViews(SampleDatabase db) - { -<b> ... - DataBinding cityKeyBinding = - new SerialBinding(db.getCityKeyFormat()); - ... - supplierByCityMap = - new StoredMap(db.getSupplierByCityIndex(), - cityKeyBinding, supplierValueBinding, true); - shipmentByPartMap = - new StoredMap(db.getShipmentByPartIndex(), - partKeyBinding, shipmentValueBinding, true); - shipmentBySupplierMap = - new StoredMap(db.getShipmentBySupplierIndex(), - supplierKeyBinding, shipmentValueBinding, true); -</b> - } -} -</pre></blockquote> -<p>In general, the indexed maps are created here in the same way as the -unindexed maps were created in the Basic example. The differences are:</p> -<p><ul type=disc> -<li>The first parameter of the -<a href="../../java/com/sleepycat/bdb/collection/StoredMap.html">StoredMap</a> - constructor is a -<a href="../../java/com/sleepycat/bdb/DataIndex.html">DataIndex</a> - rather than a -<a href="../../java/com/sleepycat/bdb/DataStore.html">DataStore</a> -. -<li>The second parameter is the index key binding rather than the -primary key binding. -</ul> -<p>For the <b>supplierByCityMap</b>, the <b>cityKeyBinding</b> must -first be created. This binding was not created in the Basic example because -the City field is not a primary key.</p> -<p>For the <b>shipmentByPartMap</b> and <b>shipmentBySupplierMap</b>, -the <b>partKeyBinding</b> and <b>supplierKeyBinding</b> are used. These -were created in the Basic example and used as the primary key bindings for the -<b>partMap</b> and <b>supplierMap</b>.</p> -<p>The value bindings--<b>supplierValueBinding</b> and -<b>shipmentValueBinding</b>--were also created in the Basic example.</p> -<p>This illustrates that bindings and formats may and should be reused where -appropriate for creating maps and other collections.</p> -<hr size=1 noshade> -<p>The following getter methods return the stored maps for use by other -classes in the example program. Convenience methods for returning entry sets -are also included.</p> -<blockquote><pre> -public class SampleViews -{ - ... -<b> public final StoredMap getShipmentByPartMap() - { - return shipmentByPartMap; - } -<p> - public final StoredMap getShipmentBySupplierMap() - { - return shipmentBySupplierMap; - } -<p> - public final StoredMap getSupplierByCityMap() - { - return supplierByCityMap; - } -<p> - public final StoredEntrySet getShipmentByPartEntrySet() - { - return (StoredEntrySet) shipmentByPartMap.entrySet(); - } -<p> - public final StoredEntrySet getShipmentBySupplierEntrySet() - { - return (StoredEntrySet) shipmentBySupplierMap.entrySet(); - } -<p> - public final StoredEntrySet getSupplierByCityEntrySet() - { - return (StoredEntrySet) supplierByCityMap.entrySet(); - } -</b>} -</pre></blockquote> -<table width="100%"><tr><td><br></td><td align=right><a href="../bdb_index/foreign.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../bdb_index/read.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p><font size=1><a href="../../sleepycat/legal.html">Copyright (c) 1996-2003</a> <a href="http://www.sleepycat.com">Sleepycat Software, Inc.</a> - All rights reserved.</font> -</body> -</html> |