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Best Practices for SAP BI using DB2 9 for z/OS - IBM Redbooks

Best Practices for SAP BI using DB2 9 for z/OS - IBM Redbooks

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Figure 8-30 ST04 Explain output<br />

Select Explain. Answer YES to the pop-up, Turn on parallelism. Refer to<br />

Figure 8-30.<br />

The Explain window gives you a graphical representation of the SQL access path<br />

and options to view table/index in<strong>for</strong>mation and the plan table.<br />

For further details on interpreting the plan table output, refer to the <strong>DB2</strong> UDB <strong>for</strong><br />

z/<strong>OS</strong> SQL Reference publication. For a more detailed discussion on this subject,<br />

refer to <strong>IBM</strong> whitepaper <strong>SAP</strong> BW Query Per<strong>for</strong>mance with <strong>DB2</strong> on ZSeries:<br />

http://www-1.ibm.com/support/docview.wss?uid=tss1wp100322<br />

ST04 - database administration<br />

Use table RSDDSTAT to identify the STATUID <strong>for</strong> the query and filter ST04<br />

Cached Statement Statistics <strong>using</strong> this value. This shows you the SQL that is<br />

relevant to the query.<br />

Chapter 8. Query and Load per<strong>for</strong>mance 173

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