117 lines
6.6 KiB
HTML
117 lines
6.6 KiB
HTML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!DOCTYPE html
|
|
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
|
<html lang="en-us" xml:lang="en-us">
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
<meta name="security" content="public" />
|
|
<meta name="Robots" content="index,follow" />
|
|
<meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' />
|
|
<meta name="DC.Type" content="reference" />
|
|
<meta name="DC.Title" content="Use host structures in COBOL applications that use SQL" />
|
|
<meta name="abstract" content="A host structure is a named set of host variables that is defined in your program's DATA DIVISION." />
|
|
<meta name="description" content="A host structure is a named set of host variables that is defined in your program's DATA DIVISION." />
|
|
<meta name="DC.subject" content="COBOL program, host structure, declaring, COBOL" />
|
|
<meta name="keywords" content="COBOL program, host structure, declaring, COBOL" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzajpcob.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzajphoststruccobol.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzajphostindicatorcobol.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzajphoststrucarraycobol.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzajphoststrucappcobol.htm" />
|
|
<meta name="DC.Relation" scheme="URI" content="rzajphostarrayindiccobol.htm" />
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1998, 2006" />
|
|
<meta name="DC.Format" content="XHTML" />
|
|
<meta name="DC.Identifier" content="rzajphoststructurecobol" />
|
|
<meta name="DC.Language" content="en-us" />
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
|
<!-- US Government Users Restricted Rights -->
|
|
<!-- Use, duplication or disclosure restricted by -->
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
|
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
|
|
<link rel="stylesheet" type="text/css" href="./ic.css" />
|
|
<title>Use host structures in COBOL applications that use SQL</title>
|
|
</head>
|
|
<body id="rzajphoststructurecobol"><a name="rzajphoststructurecobol"><!-- --></a>
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
|
<h1 class="topictitle1">Use host structures in COBOL applications that use SQL</h1>
|
|
<div><p>A <em>host structure</em> is a named set of host variables that is
|
|
defined in your program's DATA DIVISION.</p>
|
|
<div class="section"><p>Host structures have a maximum of two levels, even though the
|
|
host structure might itself occur within a multilevel structure. An exception
|
|
is the declaration of a varying-length character string, which requires another
|
|
level that must be level 49.</p>
|
|
</div>
|
|
<div class="section"><p>A host structure name can be a group name whose subordinate levels
|
|
name basic data items. For example: </p>
|
|
<pre>01 A
|
|
02 B
|
|
03 C1 PICTURE ...
|
|
03 C2 PICTURE ...</pre>
|
|
</div>
|
|
<div class="section"><p>In this example, B is the name of a host structure consisting
|
|
of the basic items C1 and C2.</p>
|
|
</div>
|
|
<div class="section"><p>When writing an SQL statement using a qualified host variable
|
|
name (for example, to identify a field within a structure), use the name of
|
|
the structure followed by a period and the name of the field. For example,
|
|
specify B.C1 rather than C1 OF B or C1 IN B. However, this guideline applies
|
|
only to qualified names within SQL statements; you cannot use this technique
|
|
for writing qualified names in COBOL statements.</p>
|
|
</div>
|
|
<div class="section"><p>A host structure is considered complete if any of the following
|
|
items are found: </p>
|
|
<ul><li>A COBOL item that must begin in area A</li>
|
|
<li>Any SQL statement (except SQL INCLUDE)</li>
|
|
</ul>
|
|
</div>
|
|
<div class="section"><p>After the host structure is defined, you can refer to it in an
|
|
SQL statement instead of listing the several host variables (that is, the
|
|
names of the data items that comprise the host structure).</p>
|
|
</div>
|
|
<div class="section"><p>For example, you can retrieve all column values from selected
|
|
rows of the table CORPDATA.EMPLOYEE with: </p>
|
|
<pre>01 PEMPL.
|
|
10 EMPNO PIC X(6).
|
|
10 FIRSTNME.
|
|
49 FIRSTNME-LEN PIC S9(4) USAGE BINARY.
|
|
49 FIRSTNME-TEXT PIC X(12).
|
|
10 MIDINIT PIC X(1).
|
|
10 LASTNAME.
|
|
49 LASTNAME-LEN PIC S9(4) USAGE BINARY.
|
|
49 LASTNAME-TEXT PIC X(15).
|
|
10 WORKDEPT PIC X(3).
|
|
…
|
|
MOVE "000220" TO EMPNO.
|
|
…
|
|
EXEC SQL
|
|
<strong>SELECT</strong> *
|
|
<strong>INTO</strong> :PEMPL
|
|
<strong>FROM</strong> CORPDATA.EMPLOYEE
|
|
<strong>WHERE</strong> EMPNO = :EMPNO
|
|
END-EXEC.</pre>
|
|
</div>
|
|
<div class="section"><p>Notice that in the declaration of PEMPL, two varying-length string
|
|
elements are included in the structure: FIRSTNME and LASTNAME.</p>
|
|
</div>
|
|
</div>
|
|
<div>
|
|
<ul class="ullinks">
|
|
<li class="ulchildlink"><strong><a href="rzajphoststruccobol.htm">Host structure in COBOL applications that use SQL</a></strong><br />
|
|
The following figure shows the syntax for the valid host structure.</li>
|
|
<li class="ulchildlink"><strong><a href="rzajphostindicatorcobol.htm">Host structure indicator array in COBOL applications that use SQL</a></strong><br />
|
|
The following figure shows the syntax for valid indicator array declarations.</li>
|
|
<li class="ulchildlink"><strong><a href="rzajphoststrucarraycobol.htm">Use host structure arrays in COBOL applications that use SQL</a></strong><br />
|
|
A host structure array is a named set of host variables that is defined in the program's Data Division and has an OCCURS clause.</li>
|
|
<li class="ulchildlink"><strong><a href="rzajphoststrucappcobol.htm">Host structure array in COBOL applications that use SQL</a></strong><br />
|
|
The following figures show the syntax for valid host structure array declarations.</li>
|
|
<li class="ulchildlink"><strong><a href="rzajphostarrayindiccobol.htm">Host array indicator structure in COBOL applications that use SQL</a></strong><br />
|
|
This figure shows the valid syntax for host structure array indicators.</li>
|
|
</ul>
|
|
|
|
<div class="familylinks">
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzajpcob.htm" title="This topic describes the unique application and coding requirements for embedding SQL statements in a COBOL program. Requirements for host structures and host variables are defined.">Code SQL statements in COBOL applications</a></div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html> |