84 lines
5.5 KiB
HTML
84 lines
5.5 KiB
HTML
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<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE html
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PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html lang="en-us" xml:lang="en-us">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
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<meta name="DC.Type" content="concept" />
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<meta name="DC.Title" content="Database files" />
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<meta name="abstract" content="A database file is one of the several types of the system object type *FILE. A database file contains descriptions of how input data is to be presented to a program from internal storage and how output data is to be presented to internal storage from a program." />
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<meta name="description" content="A database file is one of the several types of the system object type *FILE. A database file contains descriptions of how input data is to be presented to a program from internal storage and how output data is to be presented to internal storage from a program." />
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<meta name="DC.Relation" scheme="URI" content="rbafodbfcon.htm" />
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<meta name="DC.Relation" scheme="URI" content="rbafosrcc.htm" />
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<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
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<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1998, 2006" />
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<meta name="DC.Format" content="XHTML" />
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<meta name="DC.Identifier" content="rbafodbf" />
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<meta name="DC.Language" content="en-us" />
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<!-- All rights reserved. Licensed Materials Property of IBM -->
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<!-- US Government Users Restricted Rights -->
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<!-- Use, duplication or disclosure restricted by -->
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<!-- GSA ADP Schedule Contract with IBM Corp. -->
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<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
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<link rel="stylesheet" type="text/css" href="./ic.css" />
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<title>Database files</title>
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</head>
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<body id="rbafodbf"><a name="rbafodbf"><!-- --></a>
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<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
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<h1 class="topictitle1">Database files</h1>
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<div><p>A database file is one of the several types of the system object
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type *FILE. A database file contains descriptions of how input
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data is to be presented to a program from internal storage and how output
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data is to be presented to internal storage from a program.</p>
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<p>Database files contain members and records.</p>
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<div class="section" id="rbafodbf__rbafosf"><a name="rbafodbf__rbafosf"><!-- --></a><h4 class="sectiontitle">Source file</h4><p>A source file contains
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uncompiled programming code and input data needed to create some types of
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objects. It can contain source statements for such items as high-level language
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programs and data description specifications (DDS). A source file can be a
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source physical file, diskette file, tape file, or inline data file.</p>
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</div>
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<div class="section" id="rbafodbf__rbafopf"><a name="rbafodbf__rbafopf"><!-- --></a><h4 class="sectiontitle">Physical file</h4><p>A physical file is a
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database file that stores application data. It contains a description of how
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data is to be presented to or received from a program and how data is actually
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stored in the database.</p>
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<p>A physical file consists of fixed-length records
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that can have variable-length fields. It contains one record format and one
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or more members. From the perspective of the SQL interface, physical files
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are identical to tables.</p>
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</div>
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<div class="section" id="rbafodbf__rbafolf"><a name="rbafodbf__rbafolf"><!-- --></a><h4 class="sectiontitle">Logical file</h4><p>A logical file is a database
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file that logically represents one or more physical files. It contains a description
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of how data is to be presented to or received from a program. This type of
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database file contains no data, but it defines record formats for one or more
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physical files.</p>
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<p>Logical files let users access data in a sequence and
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format that is different from the physical files they represent. From the
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perspective of the SQL interface, logical files are identical to views and
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indexes.</p>
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</div>
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<div class="section" id="rbafodbf__rbafombr"><a name="rbafodbf__rbafombr"><!-- --></a><h4 class="sectiontitle">Member</h4><p>Members are different sets
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of data, each with the same format, within one database file. Before you perform
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any input or output operations on a file, the file must have at least one
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member.</p>
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<p>As a general rule, a database file has only one member, the
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one created when the file is created. If a file contains more than one member,
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each member serves as a subset of the data in the file. </p>
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</div>
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<div class="section" id="rbafodbf__rbaforcd"><a name="rbafodbf__rbaforcd"><!-- --></a><h4 class="sectiontitle">Record</h4><p>A record is a group of related
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data within a file. From the perspective of the SQL interface, records are
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identical to rows.</p>
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</div>
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</div>
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<div>
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<div class="familylinks">
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<div class="parentlink"><strong>Parent topic:</strong> <a href="rbafodbfcon.htm" title="These topics provide some of the basic database concepts for setting up or working with IBM i5/OS database files.">Database file concepts</a></div>
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</div>
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<div class="relconcepts"><strong>Related concepts</strong><br />
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<div><a href="rbafosrcc.htm" title="A source file is used when a command alone cannot supply sufficient information for creating an object.">Why source files are used</a></div>
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</div>
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</div>
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</body>
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</html>
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