Oracle 10g - optimize WHERE IS NOT NULL

Question

We have Oracle 10g and we need to query 1 table (no joins) and filter out rows where 1 of the columns is null. When we do this - WHERE OurColumn IS NOT NULL - we get a full

Answer 1

Create an index on that column.

To make sure the index is used, it should be on the index and other columns in the where.

ocdecio answered:

If you are doing a select *, then it would make sense to do a table scan rather than using the index.

That's not strictly true; an index will be used if there is an index that fits your where clause, and the query optimizer decides using that index would be faster than doing a table scan. If there is no index, or no suitable index, only then must a table scan be done.