Example: Collecting Statistics on a Constant Expression - Teradata Vantage

This example collects statistics on constant expressions, that is, an expression that does not refer to columns by name.

COLLECT STATISTICS USING SYSTEM SAMPLE
COLUMN 100,
COLUMN CURRENT_DATE+10
ON orders;

In this example, the Optimizer eliminates the constant expressions 100 and CURRENT_DATE+10 from the COLLECT STATISTICS request.

Because the rewritten expressions do not refer to columns, the Optimizer rewrites the request to use the SUMMARY option. The Optimizer also removes the USING SYSTEM SAMPLE option from the final request.

COLLECT SUMMARY STATISTICS 
ON orders;