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

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For join per<strong>for</strong>mance it is essential that the filtering dimensions are accessed<br />

be<strong>for</strong>e the E- fact table, and the dimensions providing no essential filtering are<br />

joined afterwards to the result. See Figure 8-37.<br />

Figure 8-37 Display of SQL access path<br />

This provides you with a graphical representation of the SQL access path,<br />

options to view table/index in<strong>for</strong>mation, and a view the plan table. It also gives<br />

you detailed in<strong>for</strong>mation of the SQL statement executed by the query.<br />

Chapter 8. Query and Load per<strong>for</strong>mance 181

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