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<h1 class="topictitle1">Temporary result writer job: Disadvantages with DB2<sup>®</sup> Multisystem</h1>
<div><p>The temporary result writer also has disadvantages that must be
considered when you determine its usefulness for queries.</p>
<p>The disadvantages are:</p>
<ul><li>The temporary result writer is a separate job. Consequently, it can encounter
conflicts with the main job, such as: <ul><li>The main job might have the file locked to itself. In this case, the temporary
result writer cannot access the files and cannot complete its query step.</li>
<li>The main job might have created the distributed file under commitment
control and has not yet committed the create. In this case, the temporary
result writer cannot access the file.</li>
</ul>
</li>
<li>The temporary result writer might encounter a situation
that it cannot handle in the same way as the main job. For example, if an
inquiry message is signalled, the temporary result writer might cancel, whereas
the main job can choose to ignore the message and continue on.</li>
<li>Temporary result writers are shared by all jobs on the system. If several
jobs have requests to the temporary result writers, the requests queue up
while the writers attempt to process them. <div class="note"><span class="notetitle">Note:</span> The system is shipped with
three, active temporary result writer job pairs.</div>
</li>
<li>Attempting to analyze a query (through debug messages, for example) can
be complicated if a temporary result writer is involved (because a step of
the query is run in a separate job).</li>
</ul>
<div class="note"><span class="notetitle">Note:</span> The system does not allow the temporary result writer
to be used for queries running under commitment control *CS or *ALL. This
is because the main job might have records locked in the file, which can cause
the temporary result writer to be locked out of these records and not be able
to finish.</div>
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<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="tempresult.htm" title="Temporary result writers are system-initiated jobs that are always active.">Temporary result writer with DB2 Multisystem</a></div>
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