Nested Table Scans

0     0     Edited Sep 1, 2015
Nested table scans are not presently allowed. Some functions perform a table scan. These functions are marked as [PERFORMS TABLE SCAN]. To compute the result of those functions, RB iterates through rows in the dataset. If a function performs a table scan, one must not pass as a parameter to that function any expression that contains a function or operation that requires a table scan. This would result in nested table scans, which are presently not allowed.

Example of nested table scan:
pctinrange(Q1, 1, max(Q2))

Since pctinrange and max max both perform table scans, the above syntax represents a nested table scan and thus is not presently allowed.

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