Bitmap index

A bitmap index is a type of index that uses a string of bits to quickly locate rows in a table. Bitmap indexes are normally used to index low cardinality columns in a warehouse environment.

History

Bitmap indexes was introduced in Oracle version 7.3.4.

Examples

Bitmap Index:

CREATE BITMAP INDEX emp_bitmap_idx ON big_emp(sex);

Bitmap Join Index:

CREATE BITMAP INDEX emp_dept_loc ON emp(dept.loc)
  FROM emp, dept
 WHERE emp.deptno = dept.deptno
 TABLESPACE index_ts1; 

Glossary of Terms
A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z	#