About BETWEEN and the Optimizer

Oracle 8.1.7

I am reading the documentation on optimization. Chapter 4, the Optimizer. It gives an example (6):

===

The following query uses the BETWEEN operator to select all employees with employee ID numbers between 7500 and 7800:

SELECT *
  FROM emp
  WHERE empno BETWEEN 7500 AND 7800;

To determine the selectivity of this query, the optimizer decomposes the WHERE clause condition into these two conditions:

empno >= 7500
empno <= 7800
===

This question is more out of curiosity than anything else.

Does using BETWEEN have any advantages over two separate caluses that check < and >? BETWEEN is possibly better for readability, but I am not asking about that. Does BETWEEN somehow let the optimizer tie the two WHERE clauses together where it otherwise would not?

Brian Received on Wed Dec 12 2001 - 12:35:34 CST