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295 bytes removed ,  21:38, 12 December 2010
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<p>Indexes can speedup queries by magnitudes.
Currently, four indexes exist:</p>
<ul> <li> <b>;Text Index</b>: This index speeds up text comparisons in predicates.</li> <li> <b>;Attribute Index</b>: This index speeds up attribute value comparisons in predicates.</li> <li> <b>;Full-Text Index</b>: Full-text queries are sped up by this index.</li> <li> <b>;Path Summary</b>: This index speeds up the resolution of location paths.</li> </ul>
==Examples of using the indexes==
===Text-Based Queries:===
<ul> <li>*<code>//node()[text() = 'Usability']</code></li> <li>*<code>//div[p = 'Usability' or p = 'Testing']</code></li> <li>*<code>path/to/relevant[text() = 'Usability Testing']/and/so/on</code></li> </ul>
===Attribute Index:===
<ul> <li>*<code>//node()[@align = 'right']</code></li> <li>*<code>descendant::elem[@id = '1']</code></li> <li>*<code>range/query[@id &gt;= 1 and @id &lt;= 5]</code></li> </ul>
===Full-Text Index:===
<ul> <li>*<code>//node[text() contains text 'Usability']</code></li> <li>*<code>//node[text() contains text 'Usebiliti' using fuzzy]</code></li> <li>*<code>//book[chapter contains text ('web' ftor 'WWW' using no stemming)ftand 'diversity' using stemming distance at most 5 words]</code></li> </ul>
<p>The [[full-text]] index is optimized to support all features of the XQuery Full Text
==Index data structures==
<ul> <li><b>;Text/Attribute Index</b><br/> :Both the text and attribute index are based on a balanced B-Tree and support exact matches and range queries.</li> <li><b>;Full-Text Index (Standard)</b><br/> :The standard full-text index is implemented as sorted array structure. It is optimized for simple and fuzzy searches.</li> <li><b>;Full-Text Index (Wildcards enabled)</b><br/> :A second full-text index is implemented as a compressed trie. Its needs slightly more memory than the standard full-text index, but it supports more features, such as full wildcard search.</li> </ul>
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