If the SQL statement contains search conditions for key columns, the following search strategies can be used:
Search Condition |
Search Strategy |
Equality condition for every key column |
The system accesses the corresponding table row(s) directly. |
IN Condition for a key column; and an equality condition for all other key columns (all columns that precede the column with the IN condition in the key) |
The system accesses the corresponding table row(s) directly. |
Upper and lower limits for the valid key range are created for the key columns. All search strategies, including strategies using inversions, use the knowledge of this valid search range. |