Identifying Conditions That Can Be Optimized

In addition to containing key variables, WHERE conditions must meet other requirements in order to be candidates for optimization. SAS considers using an index only for WHERE conditions that contain certain operators and functions. Therefore, the next step for SAS is to consider the operators and functions in the conditions that contain key variables.

Requirements for Optimizing a Single WHERE Condition

SAS considers using an index for a WHERE condition that contains any of the following operators and functions:
Note: For all of the following examples, assume that the data set has simple indexes on the variables Quarter, Date_ID, and Region.
Operator
Example
comparison operators

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