Integer 

Static 

1048576 (1 MB) 

Operating system dependent 

BITMAP_MERGE_AREA_SIZE is relevant only for systems containing bitmap indexes. It specifies the amount of memory Oracle uses to merge bitmaps retrieved from a range scan of the index. The default value is 1 MB. A larger value usually improves performance, because the bitmap segments must be sorted before being merged into a single bitmap.

See Also: Oracle8i Designing and Tuning for Performance for more information on setting this parameter.