SQL/MX 3.1 Installation and Management Guide (H06.23+, J06.12+)

Understanding and Planning SQL/MX Tables
HP NonStop SQL/MX Release 3.1 Installation and Management Guide—663852-001
4-19
Determining When to Use Indexes
In this example, COL1 and COL2 are key prefixes from two different indexes. NonStop
SQL/MX uses the indexes to retrieve all the rows that satisfy the predicate that COL2 =
20 or COL1 = 10:
SELECT * FROM T
WHERE COL1 = 10 OR COL2 = 20 ;
Evaluating the query by using the indexes is much more efficient than scanning the
entire table.