NUSI Space Considerations
The PERM space required during the creation of a NUSI might temporarily be much greater than the space occupied by the finished index as described by the following table.
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IF you create this sort of table … |
THEN the following peak temporary PERM space usage factors apply … |
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non-fallback or fallback with small AMP cluster size |
Estimate the temporary PERM space required when building a NUSI using the following worst case estimation equation.  where: |
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fallback |
Estimate the temporary PERM space required, assuming typical AMP cluster size, using the following equation.  This is a very conservative space estimate. For typical AMP cluster sizes, peak usage exceeds the prediction made by the model. |
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AMP cluster size, which determines the relative size of the backup subtables, is a an important factor. For information about AMP clusters, see Introduction to Teradata. A typical AMP cluster size is 4 AMPs, but the valid range varies from 2 to 8 AMPs per cluster.
NUSIs do not use spool space and are built one subtable at a time.