If the SQL statement contains search conditions for key columns, then the following search strategies are possible:
Search Condition |
Search Strategy |
Equality condition for every key column |
The appropriate row(s) are accessed directly. |
IN condition for one key column and an equality condition for all other key columns |
The appropriate row(s) are accessed 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. |