In addition to the default FP (Fast Projection) index on every column, Sybase IQ has a few other index types which work best when applied to the correct type of situation/query.
Type of Query Index Type Recommended
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As AVG / SUM argument HNG, LF, HG, FP
As MIN / MAX argument LF, HG, HNG
As COUNT argument LF, HG
As COUNT DISTINCT, SELECT DISTINCT
or GROUP BY argument LF, HG, FP
As analytical function argument LF, FP
If field does not allow duplicates LF, HG
Columns used in ad hoc join FP, HG, LF
Columns used in join index HG, LF
As LIKE argument in a WHERE clause FP
As IN argument HG, LF
In equality or inequality ( = , != ) HG, LF; also CMP
In DATEPART equality, range and
IN list predicates DATE, TIME, DTTM
In a SELECT projection list FP
In calculation expressions such as A+B FP
In range predicate WHERE clause
(>, <. >=, <=, BETWEEN) LF, HG or HNG;
also CMP, DATE, TIME, DTTM
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