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

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With all table join relationships represented, the next step is to determine where<br />

the filtering occurs <strong>for</strong> this query. The initial step in this process is to take each<br />

local predicate to the table that it refers to on the join graph. See Figure 10-11.<br />

Step 1 - Final Join Graph<br />

Z1<br />

X2<br />

Figure 10-11 The final join graph<br />

D1<br />

D6<br />

DP<br />

F<br />

D5<br />

D3 X1<br />

Chapter 10. Tips <strong>for</strong> SQL efficiency 215

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