How The Not Null Specification On A Column Improves The Netezza Perfo

1.	How The Not Null Specification On A Column Improves The Netezza Performance?
Answer» Specifying Not NULL on each COLUMN in table RESULTS in BETTER PERFORMANCE. Netezza tracks the NULL values at rowheader level. Having NULL values results in storing references to NULL values in header. If all columns are NOT NULL, then there is no record header. Specifying Not Null on each column in table results in better performance. Netezza tracks the NULL values at rowheader level. Having NULL values results in storing references to NULL values in header. If all columns are NOT NULL, then there is no record header.

How The Not Null Specification On A Column Improves The Netezza Performance?

Answer»

Specifying Not NULL on each COLUMN in table RESULTS in BETTER PERFORMANCE. Netezza tracks the NULL values at rowheader level. Having NULL values results in storing references to NULL values in header. If all columns are NOT NULL, then there is no record header.

Specifying Not Null on each column in table results in better performance. Netezza tracks the NULL values at rowheader level. Having NULL values results in storing references to NULL values in header. If all columns are NOT NULL, then there is no record header.

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