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<h1 class="topictitle1">iSeries database
frequently asked questions</h1>
<div><p>You can check the database FAQ for answers to your DB2<sup>®</sup> and Structured
Query Language (SQL) questions. Topics in the FAQ include finding informative
database resources, data sharing and migration, and several query topics. </p>
<div class="section" id="rzatefaq__question1"><a name="rzatefaq__question1"><!-- --></a><h4 class="sectiontitle">DB2 Universal Database™ for iSeries™ fundamentals</h4><ol><li><a href="#rzatefaq__basic1">What is DB2 UDB for iSeries? </a></li>
<li><a href="#rzatefaq__basic2">Is the iSeries server part of the DB2 family?</a></li>
<li><a href="#rzatefaq__basic3">How does DB2 UDB for iSeries relate to other DB2 products?</a></li>
<li><a href="#rzatefaq__basic4">What level of DB2 do I have?</a></li>
<li><a href="#rzatefaq__basic5">Does iSeries provide any sample databases?</a></li>
<li><a href="#rzatefaq__basic6">How do I install DB2?</a></li>
<li><a href="#rzatefaq__basic7">How do I authorize users to DB2? </a></li>
<li><a href="#rzatefaq__basic8">How do I administer DB2 UDB for iSeries?</a></li>
<li><a href="#rzatefaq__basic9">Can I assign my own long and short
names to tables and columns?</a></li>
</ol>
</div>
<div class="section" id="rzatefaq__question2"><a name="rzatefaq__question2"><!-- --></a><h4 class="sectiontitle">Database resources in the iSeries Information
Center</h4><ol><li><a href="#rzatefaq__resource1">Where are the DB2 manuals located?</a></li>
<li><a href="#rzatefaq__resource2">I'm having trouble printing
a PDF. What should I do?</a></li>
<li><a href="#rzatefaq__resource3">What other resources exist
to help me use the information center?</a></li>
</ol>
</div>
<div class="section" id="rzatefaq__question3"><a name="rzatefaq__question3"><!-- --></a><h4 class="sectiontitle">Data sharing and database migration</h4><ol><li><a href="#rzatefaq__data1">How do I move data between DB2 and
other systems?</a></li>
<li><a href="#rzatefaq__data2">How do I migrate existing databases
to DB2 UDB
for iSeries?</a></li>
<li><a href="#rzatefaq__data3">Can I store XML data in DB2 UDB for iSeries?</a></li>
<li><a href="#rzatefaq__data4">Can I connect to a DB2 database that
is on a non-iSeries server from my iSeries server?</a></li>
</ol>
</div>
<div class="section" id="rzatefaq__question4"><a name="rzatefaq__question4"><!-- --></a><h4 class="sectiontitle">Query for iSeries</h4><ol><li><a href="#rzatefaq__qi1">How can I find all the queries that
accessed a specific file?</a></li>
<li><a href="#rzatefaq__qi2">Does IBM<sup>®</sup> provide any graphical query interfaces
for the iSeries server?</a></li>
</ol>
</div>
<div class="section" id="rzatefaq__question5"><a name="rzatefaq__question5"><!-- --></a><h4 class="sectiontitle">SQL-based queries</h4><ol><li><a href="#rzatefaq__qsql1">How can I join two members of the
same table?</a></li>
<li><a href="#rzatefaq__qsql2">How can I run SQL statements from
a text file?</a></li>
<li><a href="#rzatefaq__qsql3">How can I write an SQL query that
lists a set of detail records with a total at the bottom?</a></li>
<li><a href="#rzatefaq__qsql4">How can I select rows based on
the current date in numeric or character fields?</a></li>
<li><a href="#rzatefaq__qsql5">Why is my query performing
poorly after an upgrade to a newer release of i5/OS™?</a></li>
<li><img src="./delta.gif" alt="Start of change" /><a href="#rzatefaq__qsql6">Can I create an alias
on a server for a table, view, or physical file that is on another server?</a><img src="./deltaend.gif" alt="End of change" /></li>
<li><img src="./delta.gif" alt="Start of change" /><a href="#rzatefaq__qsql7">When the first member
of a multimember database file has the same name as the file, it is the only
member of the file that you can access using SQL. How can I access another
member using SQL?</a><img src="./deltaend.gif" alt="End of change" /></li>
</ol>
</div>
<div class="section" id="rzatefaq__question6"><a name="rzatefaq__question6"><!-- --></a><h4 class="sectiontitle">SQL messages</h4><ol><li><a href="#rzatefaq__message1">When are SQL messages displayed?</a></li>
<li><a href="#rzatefaq__message2">What does SQL0901 message code
mean?</a></li>
<li><a href="#rzatefaq__message3">Where can I find a listing of
SQL messages and SQL codes?</a></li>
</ol>
</div>
<div class="section" id="rzatefaq__question7"><a name="rzatefaq__question7"><!-- --></a><h4 class="sectiontitle">SQL packages</h4><ol><li><a href="#rzatefaq__package1">What are SQL packages?</a></li>
<li><a href="#rzatefaq__package2">What are the advantages of using
SQL packages?</a></li>
<li><a href="#rzatefaq__package3">What data is stored in an SQL
package?</a></li>
<li><a href="#rzatefaq__package4">How can I tell what statements
are in an SQL package?</a></li>
<li><a href="#rzatefaq__package5">How can I tell if the SQL package
is being used?</a></li>
</ol>
</div>
<div class="section" id="rzatefaq__question8"><a name="rzatefaq__question8"><!-- --></a><h4 class="sectiontitle">Stored procedures</h4><ol><li><a href="#rzatefaq__store1">How can I view the contents of
a result set and the output parameters from a stored procedure call?</a></li>
<li><a href="#rzatefaq__store2">Can existing RPG or COBOL programs
be used as stored procedures?</a></li>
<li><a href="#rzatefaq__store3">I do a CREATE PROCEDURE that contains
SQL statements that reference user-defined functions. Before calling the procedure,
I do a SET PATH so the functions are found. Why aren't the functions found
when I call the procedure?</a></li>
<li><a href="#rzatefaq__store4">How do I find out if a
stored procedure exists, in what library it exists, and what the attributes
of the stored procedure are?</a></li>
</ol>
</div>
<div class="section" id="rzatefaq__question9"><a name="rzatefaq__question9"><!-- --></a><h4 class="sectiontitle">Triggers</h4><ol><li><a href="#rzatefaq__trigger1">What is a trigger?</a></li>
<li><a href="#rzatefaq__trigger2">Why does my trigger program
not work after upgrading i5/OS?</a></li>
</ol>
</div>
<div class="section" id="rzatefaq__basic"><a name="rzatefaq__basic"><!-- --></a><h4 class="sectiontitle">DB2 Universal Database for iSeries fundamentals</h4><ol><li id="rzatefaq__basic1"><a name="rzatefaq__basic1"><!-- --></a><span><strong>What is DB2 UDB for iSeries?</strong></span><p>DB2 UDB for iSeries is
the relational database manager that is fully integrated on your iSeries server.
Because it is integrated, DB2 UDB for iSeries is easy to use and manage. DB2 UDB
for iSeries also
provides functions such as triggers, stored procedures, and dynamic bitmapped
indexing that serve a wide variety of application types. These applications
range from traditional host-based applications to client/server solutions
to business intelligence applications.</p>
<p>The history of DB2 UDB for iSeries began
in the late 1980s with the integration of a fully relational, though nameless,
database on the first AS/400<sup>®</sup> systems. In 1995, this database joined the DB2 brand,
adopting the name DB2/400. In 1999, the DB2 UDB branding was added.</p>
<p>As an
interface to DB2 UDB
for iSeries,
the DB2 Query
Manager and SQL Development Kit for iSeries adds an interactive query and
report writing interface, as well as precompilers and tools to assist in writing
SQL application programs in high-level programming languages. Conforming to
the industry standard SQL, the SQL implementation for <span class="keyword">i5/OS</span> allows you to define, manipulate, query, and
control access to your iSeries data. It works equally well with <span class="keyword">i5/OS</span> files and
SQL tables.</p>
<p><a href="#rzatefaq__question1">Back
to questions</a></p>
</li>
<li id="rzatefaq__basic2"><a name="rzatefaq__basic2"><!-- --></a><span><strong>Is the iSeries server part of the DB2 family?</strong></span><p>Yes. DB2 UDB
for iSeries is
the newest member of the DB2 UDB product line, which also includes DB2 UDB and DB2
Universal Database™ for zSeries<sup>®</sup>. DB2 UDB, the founding member of the product
line, is the single product available across all UNIX<sup>®</sup>, Windows NT<sup>®</sup>, and OS/2<sup>®</sup> operating
systems.</p>
<p><a href="#rzatefaq__question1">Back
to questions</a></p>
</li>
<li id="rzatefaq__basic3"><a name="rzatefaq__basic3"><!-- --></a><span><strong>How does DB2 UDB for iSeries relate to other DB2 products?</strong></span><p>Each
member of the DB2 UDB
product line has its own unique code-base, functions, and different SQL syntax.
There is, however, technology sharing across the DB2 UDB brand members. To learn about the
relationships between the DB2 UDB products, see the following information:</p>
<ul><li><a href="http://www-1.ibm.com/servers/enable/site/db2/db2common.html" target="_blank">DB2 Universal Database: Selected Common
SQL Features for Developers of Portable SQL Applications</a><img src="www.gif" alt="Link outside information center" /> contains information about the SQL features available
on the DB2 UDB
products.</li>
<li><a href="http://www-1.ibm.com/servers/enable/site/education/ibo/record.html?db2400" target="_blank">What Does DB2 UDB on the iSeries Really Mean?</a><img src="www.gif" alt="Link outside information center" /> explains the position of DB2 UDB for iSeries in the DB2 family, with details about functionality.</li>
<li><a href="http://www-1.ibm.com/servers/enable/site/db2/porting.html" target="_blank">DB2 Porting Information</a><img src="www.gif" alt="Link outside information center" /> provides guides to help you move data between DB2 UDB
products. The porting guides also provide a brief history of the DB2 UDB brand.</li>
</ul>
<p><a href="#rzatefaq__question1">Back to questions</a></p>
</li>
<li id="rzatefaq__basic4"><a name="rzatefaq__basic4"><!-- --></a><span><strong>What level of DB2 do I have?</strong></span><p>If you are using
an iSeries server,
you have DB2 UDB
for iSeries.
The level of DB2 UDB
for iSeries is
based on the <span class="keyword">i5/OS</span> operating
system, and is independent of the DB2 versioning scheme. Because DB2 UDB for iSeries is
included with the <span class="keyword">i5/OS</span> operating
system, the version, release, and modification level of DB2 is the same
as that of your operating system. This is typically expressed as VxRyMz, where
x is the version, y is the release, and m is the modification. If you do not
know what version, release, and modification of <span class="keyword">i5/OS</span> you have, use the following steps:</p>
<ol type="a"><li>In iSeries Navigator,
right click your server.</li>
<li>Select <span class="uicontrol">Properties</span>.</li>
<li>If it is not already selected, click the <span class="uicontrol">General </span> tab.</li>
</ol>
<p><a href="#rzatefaq__question1">Back to questions</a></p>
</li>
<li id="rzatefaq__basic5"><a name="rzatefaq__basic5"><!-- --></a><span><strong>Does the iSeries server provide any sample databases?</strong></span><p>Yes.
You can find the sample tables and the system-provided stored procedure to
create them in <a href="../sqlp/rbafysamptblx.htm">DB2 UDB
for iSeries sample
tables</a> of the SQL programming topic.</p>
<p><a href="#rzatefaq__question1">Back to questions</a></p>
</li>
<li id="rzatefaq__basic6"><a name="rzatefaq__basic6"><!-- --></a><span><strong>How do I install DB2?</strong></span><p>You don't need to
install DB2.
It is shipped as a part of i5/OS at every release.</p>
<p><a href="#rzatefaq__question1">Back to questions</a></p>
</li>
<li id="rzatefaq__basic7"><a name="rzatefaq__basic7"><!-- --></a><span><strong>How do I authorize users to DB2?</strong></span><p>DB2 object access
can be controlled using SQL GRANT and REVOKE statements along with i5/OS security
interfaces. See <a href="../dbp/rbafosecuc.htm">Secure
a database</a> in the Database programming topic. iSeries Navigator can also be used to
authorize users. For more information, see <a href="../dbp/rbafoautuon.htm">Authorize a user or group using iSeries Navigator</a>.</p>
<p><a href="#rzatefaq__question1">Back to questions</a></p>
</li>
<li id="rzatefaq__basic8"><a name="rzatefaq__basic8"><!-- --></a><span><strong>How do I administer DB2 UDB for iSeries?</strong></span><p>You
can administer DB2 UDB
for iSeries using iSeries Navigator.
Within iSeries Navigator
there is a tool for working with databases. You can work either from a traditional
tree view of you database, or from a visual representation of the database
objects called Database Navigator. For details about using Database Navigator,
see <a href="../rzatc/rzatcdbmap.htm">Map your database
using Database Navigator maps</a>.</p>
<p><a href="#rzatefaq__question1">Back to questions</a></p>
</li>
<li id="rzatefaq__basic9"><a name="rzatefaq__basic9"><!-- --></a><span><strong></strong><strong>Can I assign my own long and short names to
tables and columns?</strong></span><p>Yes. See <a href="http://www-1.ibm.com/servers/eserver/iseries/db2/longsqltable.htm" target="_blank">Co-existing with "long" SQL table and column names</a><img src="www.gif" alt="Link outside information center" /> for instructions.</p>
<p><a href="#rzatefaq__question1">Back to questions</a></p>
</li>
</ol>
</div>
<div class="section" id="rzatefaq__resource"><a name="rzatefaq__resource"><!-- --></a><h4 class="sectiontitle">Database resources in the iSeries Information
Center</h4><ol><li id="rzatefaq__resource1"><a name="rzatefaq__resource1"><!-- --></a><span><strong>Where are the DB2 manuals located?</strong></span><p>The Softcopy
Library was integrated into the iSeries Information Center in V5R1. You
can find database manuals by following the (PDFs) link in the information
center navigation bar under the Database topic.</p>
<p><a href="#rzatefaq__question2">Back to questions</a></p>
</li>
<li id="rzatefaq__resource2"><a name="rzatefaq__resource2"><!-- --></a><span><strong>I'm having trouble printing a PDF. What should I
do?</strong></span><p>It is recommended that you save PDF files locally for ease
in viewing and printing. To save the PDF, follow these steps:</p>
<ol type="a"><li>Right-click the PDF in your browser.</li>
<li>Click <span class="uicontrol">Save Target As...</span></li>
<li>Navigate to the directory in which to save the PDF. </li>
<li>Click <span class="uicontrol">Save</span>.</li>
</ol>
<p><a href="#rzatefaq__question2">Back to questions</a></p>
</li>
<li id="rzatefaq__resource3"><a name="rzatefaq__resource3"><!-- --></a><span><strong>What other resources exist to help me use the information
center?</strong></span><p>See the <a href="../rzahg/rzahgicfaq.htm">Frequently
asked questions about the information center</a> topic. This FAQ contains
tips that make using the information center easier. You can also find help
by clicking the help button in the upper right of your screen.</p>
<p><a href="#rzatefaq__question2">Back to questions</a></p>
</li>
</ol>
</div>
<div class="section" id="rzatefaq__data"><a name="rzatefaq__data"><!-- --></a><h4 class="sectiontitle">Data sharing and database migration</h4><ol><li id="rzatefaq__data1"><a name="rzatefaq__data1"><!-- --></a><span><strong>How do I move data between DB2 and other systems?</strong></span><p>You can
use the <a href="../cl/cpyfrmimpf.htm">Copy From Import File
(CPYFRMIMPF)</a> and <a href="../cl/cpytoimpf.htm">Copy
To Import File (CPYTOIMPF)</a> commands to import (load) or export (unload)
data from and to the iSeries server. See the <a href="../rzahf/rzahfimportexportdata.htm">Import
and export data between systems</a> topic for instructions.</p>
<p><a href="#rzatefaq__question3">Back to questions</a></p>
</li>
<li id="rzatefaq__data2"><a name="rzatefaq__data2"><!-- --></a><span><strong>How do I migrate existing databases to DB2 UDB for iSeries?</strong></span><p>IBM provides
several guides to help you move data into DB2 UDB for iSeries from other databases, such as
Oracle and SQL Server. See <a href="http://www-1.ibm.com/servers/enable/site/db2/porting.html" target="_blank">DB2 Porting Information</a><img src="www.gif" alt="Link outside information center" /> for the guides. </p>
<p><a href="#rzatefaq__question3">Back to questions</a></p>
</li>
<li id="rzatefaq__data3"><a name="rzatefaq__data3"><!-- --></a><span><strong>Can I store XML data in DB2 UDB for iSeries?</strong></span><p>Yes. See the <a href="../books/sc189179.pdf" target="_blank">XML Extender Administration
and Programming</a><img src="wbpdf.gif" alt="Link to PDF" /> manual
for tutorials on how to set up a database using provided sample data, how
to map SQL data to an XML document, how to store XML documents in the database,
and how to search and extract data from the XML documents. </p>
<p><a href="#rzatefaq__question3">Back to questions</a></p>
</li>
<li id="rzatefaq__data4"><a name="rzatefaq__data4"><!-- --></a><span><strong>Can I connect to a DB2 database that is on a non-iSeries server
from my iSeries server?</strong></span><p>Yes.
You can learn more in <a href="../ddp/rbal1xplat.htm">User
FAQs</a> of the Distributed database programming topic.</p>
<p><a href="#rzatefaq__question3">Back to questions</a></p>
</li>
</ol>
</div>
<div class="section" id="rzatefaq__qi"><a name="rzatefaq__qi"><!-- --></a><h4 class="sectiontitle">Query for iSeries</h4><ol><li id="rzatefaq__qi1"><a name="rzatefaq__qi1"><!-- --></a><span><strong>How can I find all the queries that accessed a specific
file?</strong></span><p>You can follow these steps to produce a report of all the
queries containing the file name:</p>
<ol type="a"><li>Copy the code in <a href="rzatefindqueryex.htm#examplefindingthequeriesthataccessedaspecificfile">Example: Find the queries that accessed a specific file</a>,
replacing &amp;LIBRARY and &amp;FILE with your library and file names.</li>
<li>Create the command FFINQ using the <a href="../cl/crtcmd.htm">Create
Command (CRTCMD)</a> command.</li>
<li>Specify GETQRYPRM as the program to process command.</li>
</ol>
<p><a href="#rzatefaq__question4">Back to questions</a></p>
</li>
<li id="rzatefaq__qi2"><a name="rzatefaq__qi2"><!-- --></a><span><strong>Does IBM provide any graphical query interfaces for the iSeries server?</strong></span><p>The graphical query interface software provided for iSeries includes <a href="http://www-4.ibm.com/software/data/qmf" target="_blank"> DB2 Query
Management Facility</a><img src="www.gif" alt="Link outside information center" /> and <a href="http://www-306.ibm.com/software/data/db2imstools/db2tools/db2wqt" target="_blank">DB2 Web Query Tool</a><img src="www.gif" alt="Link outside information center" />. </p>
<p><a href="#rzatefaq__question4">Back
to questions</a></p>
</li>
</ol>
</div>
<div class="section" id="rzatefaq__qsql"><a name="rzatefaq__qsql"><!-- --></a><h4 class="sectiontitle">SQL-based queries</h4><ol><li id="rzatefaq__qsql1"><a name="rzatefaq__qsql1"><!-- --></a><span><strong>How can I join two members of the same table?</strong></span><p>You can join two members of the same table by creating an
alias for one of the members and joining them using the alias. To create an
alias using SQL, see the <a href="../sqlp/rbafycreatingalias.htm">Create
and use ALIAS names</a> or <a href="../rzahf/rzahfcreatedbotable.htm">Create database objects</a> topic.</p>
<p><a href="#rzatefaq__question5">Back to questions</a></p>
</li>
<li id="rzatefaq__qsql2"><a name="rzatefaq__qsql2"><!-- --></a><span><strong>How can I run SQL statements from a text file?</strong></span><p>You can run SQL statements from a text file using the <a href="../cl/runsqlstm.htm">Run SQL Statements (RUNSQLSTM)</a> command.
Or, you can use Run SQL Scripts from iSeries Navigator to run a text file
on your PC or in the integrated file system. See <a href="../rzatc/rzatcrunscript.htm">Query
your database using the Run SQL Scripts interface</a>.</p>
<p><a href="#rzatefaq__question5">Back to questions</a></p>
</li>
<li id="rzatefaq__qsql3"><a name="rzatefaq__qsql3"><!-- --></a><span><strong>How can I write an SQL query that lists a set of detail
rows with a total at the bottom?</strong></span><div class="p">You can use a <tt>UNION</tt> operation
to append the total as a row at the end of the list of items, as illustrated
in the following example: <pre><strong>SELECT</strong> 'ITEM' <strong>AS</strong> ROWTYPE, PARTID, PRICE
<strong>FROM</strong> PART
<strong>UNION</strong>
<strong>SELECT</strong> 'TOTAL' <strong>AS</strong> ROWTYPE, 0 <strong>AS</strong> PARTID, <strong>SUM</strong>( PRICE ) <strong>AS</strong> PRICE
<strong>FROM</strong> PART
<strong>ORDER BY</strong> ROWTYPE, PARTID</pre>
</div>
<p>To make sure that the total
row is at the end of the result set, you must include the <tt>Order By</tt> clause.</p>
<p><a href="#rzatefaq__question5">Back to questions</a></p>
</li>
<li id="rzatefaq__qsql4"><a name="rzatefaq__qsql4"><!-- --></a><span><strong>How can I select rows based on the current date in numeric
or character fields?</strong></span><p>The SQL <tt>CurDate</tt> function returns
a date value, which cannot be directly compared to a number or an unformatted
character value. You must do some conversion before the comparison. Use SQL
functions to get the year, month, and day of the date as integers, and then
create a numeric date in the form YYYYMMDD. See the code in <a href="rzatecurdateex.htm#rzatecurdateex">Example: Select records based on the current date</a>.</p>
<p><a href="#rzatefaq__question5">Back to questions</a></p>
</li>
<li id="rzatefaq__qsql5"><a name="rzatefaq__qsql5"><!-- --></a><span><strong>Why is my query performing poorly after an upgrade to
a newer release of <span class="keyword">i5/OS</span>?</strong></span><p>There can be some query performance problems if you recently
upgraded from V4R4 to a newer release or version. See <a href="http://www.ibm.com/support/docview.wss?uid=nas1f865c1d0f9fa573f86256a5b0049ffc1" target="_blank"> IBM DB2 UDB Query Performance Behavior Changes Since R440</a><img src="www.gif" alt="Link outside information center" /> for a possible
solution.</p>
<p><a href="#rzatefaq__question5">Back
to questions</a></p>
</li>
<li id="rzatefaq__qsql6"><a name="rzatefaq__qsql6"><!-- --></a><img src="./delta.gif" alt="Start of change" /><span><strong>Can I create an alias on a server for a
table, view, or physical file that is on another server?</strong></span><p>No. When
you create an alias, make sure that the table, view, or physical file you
create it for is on the current server. For more information, see <a href="../db2/rbafzmsthcalias.htm">CREATE ALIAS</a>, with some syntax examples.</p>
<p><a href="#rzatefaq__question5">Back to questions</a></p>
<img src="./deltaend.gif" alt="End of change" /></li>
<li id="rzatefaq__qsql7"><a name="rzatefaq__qsql7"><!-- --></a><img src="./delta.gif" alt="Start of change" /><span><strong>When the first member of a multimember
database file has the same name as the file, it is the only member of the
file that you can access using SQL. How can I access another member using
SQL?</strong></span><p>You can create an alias to point at the first member you want
to access.</p>
<div class="p">Example 2: Create an alias named SALES_JANUARY on the JANUARY
member of the SALES table. The sales table has 12 members (one for each month
of the year).<pre>CREATE ALIAS SALES_JANUARY
FOR SALES(JANUARY)</pre>
For the complete example in the SQL reference,
see <a href="../db2/rbafzmsthcalias.htm">CREATE ALIAS</a>.</div>
<p><a href="#rzatefaq__question5">Back to questions</a></p>
<img src="./deltaend.gif" alt="End of change" /></li>
</ol>
</div>
<div class="section" id="rzatefaq__message"><a name="rzatefaq__message"><!-- --></a><h4 class="sectiontitle">SQL messages</h4><ol><li id="rzatefaq__message1"><a name="rzatefaq__message1"><!-- --></a><span><strong>When are SQL messages displayed?</strong></span><p>SQL messages
are displayed when a DB2 UDB for iSeries returns an error or code to the
application that uses it. The message text is displayed or logged at run time.</p>
<p><a href="#rzatefaq__question6">Back to questions</a></p>
</li>
<li id="rzatefaq__message2"><a name="rzatefaq__message2"><!-- --></a><span><strong>What does the SQL0901 message mean?</strong></span><p>SQL0901:
An SQL system error has occurred. This is the general message for all errors.
For more information about SQL0901, see the <a href="../rzala/rzalakickoff.htm">SQL
messages and codes</a> topic.</p>
<p><a href="#rzatefaq__question6">Back to questions</a></p>
</li>
<li id="rzatefaq__message3"><a name="rzatefaq__message3"><!-- --></a><span><strong>Where can I find a list of SQL messages and SQL codes?</strong></span><p>You
can find a complete list of SQL messages and codes in the <a href="../rzala/rzalakickoff.htm">SQL messages and codes</a> topic. Or use <a href="../rzala/rzalafinder.htm">SQL message finder</a>.</p>
<p>An
application can also send the SQL message corresponding to any SQLCODE to
the job log by specifying the message ID and the replacement text on the CL
commands <a href="../cl/rtvmsg.htm">Retrieve Message (RTVMSG)</a>, <a href="../cl/sndpgmmsg.htm">Send Program Message (SNDPGMMSG)</a>,
and <a href="../cl/sndusrmsg.htm">Send User Message (SNDUSRMSG)</a>.</p>
<p><a href="#rzatefaq__question6">Back to questions</a></p>
</li>
</ol>
</div>
<div class="section" id="rzatefaq__package"><a name="rzatefaq__package"><!-- --></a><h4 class="sectiontitle">SQL packages</h4><ol><li id="rzatefaq__package1"><a name="rzatefaq__package1"><!-- --></a><span><strong>What are SQL packages?</strong></span><p>SQL packages are
permanent objects that are used to store information related to prepared SQL
statements. They are used by open database connectivity (ODBC) support when
the Extended Dynamic box is checked on a data source. They are also used by
applications that use an API.</p>
<p><a href="#rzatefaq__question7">Back to questions</a></p>
</li>
<li id="rzatefaq__package2"><a name="rzatefaq__package2"><!-- --></a><span><strong>What are the advantages of using SQL packages?</strong></span><p>Because
SQL packages are a shared resource, when a statement is prepared, the information
is available to all the users of the package. This saves processing time,
especially in an environment when many users are using the same or similar
statements. Because SQL packages are permanent, this information is also saved
across job initiation and end, and is also saved across system restarts. In
fact, SQL packages can be saved and restored on other systems. By comparison,
dynamic SQL requires that each user go through the preparatory processing
for a particular statement, and this must be done every time the user starts
the application.</p>
<p>SQL packages also allow the system to accumulate statistical
information about the SQL statements that result in better decisions about
how long to keep cursors open internally and how to best process the data
needed for the query. This information is shared across users and retained
for future use. In the case of dynamic SQL, this information must be gathered
by every job and every user.</p>
<p><a href="#rzatefaq__question7">Back to questions</a></p>
</li>
<li id="rzatefaq__package3"><a name="rzatefaq__package3"><!-- --></a><span><strong>What data is stored in an SQL package?</strong></span><p>The
SQL package contains all the necessary information to run the prepared statement.
This includes registry of the statement name, the statement text, the internal
parse tree for the statement, definitions of all the tables and fields involved
in the statement, and the query access plan needed to access the tables at
run time.</p>
<p><a href="#rzatefaq__question7">Back
to questions</a></p>
</li>
<li id="rzatefaq__package4"><a name="rzatefaq__package4"><!-- --></a><span><strong>How can I tell what statements are in an SQL package</strong>?</span><p>Use
the <a href="../cl/prtsqlinf.htm">Print SQL Information (PRTSQLINF)</a> command
to produce a formatted report that shows the SQL statement and information
about the access plan used to access the data.</p>
<p><a href="#rzatefaq__question7">Back to questions</a></p>
</li>
<li id="rzatefaq__package5"><a name="rzatefaq__package5"><!-- --></a><span><strong>How can I tell if the SQL package is being used?</strong></span><div class="p">Use
the <a href="../cl/prtsqlinf.htm">Print SQL Information (PRTSQLINF)</a> command
to produce a formatted report that shows the SQL statement and information
about the access plan used to access the data. Use the database monitor to
log information about SQL processing on the system. It includes the name of
the package in the SQL summary records. The following statement shows the
package, the SQL operation, and the statement text:<pre>SELECT qqc103, qqc21, qq1000 from &lt;db monitor file&gt;</pre>
</div>
<p>For
ODBC, you can also look in the job log for the message <tt>Extended Dynamic
has been disabled</tt> to determine if ODBC was unable to use an SQL package.</p>
<p><a href="#rzatefaq__question7">Back to questions</a></p>
</li>
</ol>
<p>For more SQL package FAQs, see the <a href="http://www-1.ibm.com/servers/eserver/iseries/db2/sqlperffaq.htm" target="_blank">DB2
Universal Database for iSeries Frequently Asked Questions: Improving Performance
with SQL Packages</a><img src="www.gif" alt="Link outside information center" />.</p>
</div>
<div class="section" id="rzatefaq__store"><a name="rzatefaq__store"><!-- --></a><h4 class="sectiontitle">Stored procedures</h4><ol><li id="rzatefaq__store1"><a name="rzatefaq__store1"><!-- --></a><span><strong>How can I view the contents of a result set and the
output parameters from a stored procedure call?</strong></span><p>Use Run SQL Scripts
to run the procedure in iSeries Navigator. First, open the Run SQL Scripts
window. Then, call the stored procedure using the <a href="../db2/rbafzmstcallsta.htm">CALL</a> statement,
pass the parameters to the statement, and then run the procedure. The parameters
are returned to the Result Set tab, and the output parameters are returned
to the Messages tab.</p>
<p><a href="#rzatefaq__question8">Back
to questions</a></p>
</li>
<li id="rzatefaq__store2"><a name="rzatefaq__store2"><!-- --></a><span><strong>Can existing RPG or COBOL programs be used as stored
procedures?</strong></span><p>Yes. DB2 UDB for iSeries supports external stored procedures,
which allows existing high-level programs to be called as stored procedures.
The CREATE PROCEDURE statement is used to register these programs as stored
procedures.</p>
<p><a href="#rzatefaq__question8">Back
to questions</a></p>
</li>
<li id="rzatefaq__store3"><a name="rzatefaq__store3"><!-- --></a><span><strong>I do a CREATE PROCEDURE that contains SQL statements
that reference user-defined functions. Before calling the procedure, I do
a SET PATH so the functions are found. Why aren't the functions found when
I call the procedure?</strong></span><p>The SET PATH statement must be done before
the CREATE PROCEDURE statement. The path for static statements in a precompiled
program is determined when the program is created. In the case of CREATE PROCEDURE,
we create an SQL C program. Dynamic statements in the procedure use the current
path, but the static statements in the procedure use the path that was used
at the time of creation. This is also true for the CREATE FUNCTION statement. </p>
<p><a href="#rzatefaq__question8">Back to questions</a></p>
</li>
<li id="rzatefaq__store4"><a name="rzatefaq__store4"><!-- --></a><span><strong>How do I find out if a stored procedure exists, in
what library it exists, and what the attributes of the stored procedure are?</strong></span><div class="p">To
see the stored procedures on the system, you need to query the SYSPROCS catalog
view. For example: <pre>SELECT * from sysprocs where routine_name = 'MYPROC' and routine_schema = 'MYLIB'</pre>
This
checks to see if there is a stored procedure named <em>myproc</em> in <em>mylib</em>.
If you do not know the library, do not include the <em>routine_schema</em> part
of the search condition in the query. See <a href="../db2/rbafzmstcatalogtbls.htm"> iSeries catalog
tables and views</a> in the SQL reference topic for the definition of all
the columns for the SYSPROCS catalog. You might also be interested in the
SYSPARMS catalog, which contains the parameter definitions for a procedure.</div>
<p><a href="#rzatefaq__question8">Back to questions</a></p>
</li>
</ol>
</div>
<div class="section" id="rzatefaq__trigger"><a name="rzatefaq__trigger"><!-- --></a><h4 class="sectiontitle">Triggers</h4><ol><li id="rzatefaq__trigger1"><a name="rzatefaq__trigger1"><!-- --></a><span><strong>What is a trigger?</strong></span><p>A trigger is a set
of actions that are run automatically when a specified change or read operation
is performed on a specified table or on a specified physical database file.
For more information, see <a href="../dbp/rbaforzahftra.htm">Trigger
automatic events in your database</a>.</p>
<p>Beginning in V5R1, you can
also use SQL triggers. The SQL CREATE TRIGGER statement provides a way for
the database management system to actively control, monitor, and manage a
group of tables whenever an insert, update, or delete operation is performed.
The statements specified in the SQL trigger are run each time an SQL insert,
update, or delete operation is performed. An SQL trigger can call stored procedures
or user-defined functions to perform additional processing when the trigger
is run. For more information, see <a href="../sqlp/rbafysqltrig.htm">SQL
triggers</a>.</p>
<p><a href="#rzatefaq__question9">Back
to questions</a></p>
</li>
<li id="rzatefaq__trigger2"><a name="rzatefaq__trigger2"><!-- --></a><span><strong>Why does my trigger program not
work after upgrading i5/OS?</strong></span><p>The offset of your record might have
changed. For several releases in the past, the offset did not change. It did,
however, change for V5R1 and might change in subsequent releases. The easiest
solution is to always code your trigger programs to use the offsets and lengths
passed in the trigger buffer. For a summary of fields in the trigger buffer,
see <a href="../dbp/rbaforzahftrd.htm">Trigger buffer field
descriptions</a>.</p>
<p><a href="#rzatefaq__question9">Back
to questions</a></p>
</li>
</ol>
</div>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="rzatekickoff.htm" title="These topics provide solutions to common questions and problems for the DB2 for iSeries database.">Troubleshooting</a></div>
</div>
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