Avoid queries with condition IS NULL

Avoid queries with condition IS NULL ( Rather create column with NOT NULL Default value). If IS NULL is required, consider replacing it with a NVL call and a function based index, while this may not help with outer joins, it will help with IS NULL type selects. select count(*) from test where object_id is null; ( TABLE ACCESS (FULL)) select count(*) from test where nvl(object_id,-1)=-1; - INDEX (RANGE SCAN) OF 'FBI_TEST' (NON-UNIQUE)"