<docbook><section><title>WhatDoesOCIPrefetchMemoryDo</title><para> </para><bridgehead class="http://www.w3.org/1999/xhtml:h2">What does <ulink url="OCIPrefetchMemory">OCIPrefetchMemory</ulink> do?</bridgehead>
<para><ulink url="OCIPrefetchMemory">OCIPrefetchMemory</ulink> and <ulink url="OCIPrefetchRows">OCIPrefetchRows</ulink> control parameters relating to the Oracle OCI&#39;s prefetching facility.
 However, use of this facility has been disabled in the <ulink url="OpenLink">OpenLink</ulink> agent and Lite driver because of problems experienced with Oracle 8.x and indicator variables.</para><para>To minimize server round trips and maximize performance, the OCI can prefetch rows when executing a query.
 This prefetching operates independently of <ulink url="OpenLink">OpenLink</ulink>&#39;s prefetching facillty.
 OCI prefetching can be customized by setting two attributes; OCI_ ATTR_ PREFETCH_ ROWS and OCI_ ATTR _ PREFETCH_ MEMORY.
 The <ulink url="OCIPrefetchMemory">OCIPrefetchMemory</ulink> and <ulink url="OCIPrefetchRows">OCIPrefetchRows</ulink> settings in the <ulink url="OpenLink">OpenLink</ulink> setup dialogs map directly to these, two OCI attributes.</para><para><ulink url="OCIPrefetchMemory">OCIPrefetchMemory</ulink> sets the memory allocated for rows to be prefetched.
 The application then fetches as many rows as will fit into that much memory.</para><para><ulink url="OCIPrefetchRows">OCIPrefetchRows</ulink> sets the number of rows to be prefetched.</para><para>When both of these attributes are set, the OCI prefetches rows up to the <ulink url="OCIPrefetchRows">OCIPrefetchRows</ulink> limit or until the <ulink url="OCIPrefetchMemory">OCIPrefetchMemory</ulink> limit is reached, if this is lower.
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