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SQL Development
Optimizing Query Performance
:
Understanding optimization
:
Optimizer phases
:
GROUP BY optimization
GROUP BY optimization
GROUP BY optimization allows the SQL engine to select index scan and to perform STREAM aggregation for GROUP BY columns. The two techniques of GROUP BY optimizations are as follows:
1. Re-order GROUP BY columns
2. Considering Equi-Constant Predicates
In this section:
Re-order GROUP BY columns
Considering Equi-Constant Predicates
1. Re-order GROUP BY columns
