Patent ID: 7467150
Filing Date: 2008-12-16
Classification: H03M,Y10S

Abstract:
1. A method for compressing bitmaps of an index of a database table, generating a plurality of atoms that together represent a series of bitmaps, wherein each bitmap of said series of bitmaps contains a series of bytes, with bit positions that each corresponds to a record stored in a data block of a database and that indicates whether the record satisfies a particular criteria; wherein the series of bitmaps includes one bitmap that includes a different number of bytes than another bitmap in the series of bitmaps; wherein the series of bitmaps includes a plurality of gaps of one or more bytes, each of the one or more bytes having no bit positions set; and wherein each atom of said plurality of atoms that describes a gap of said plurality of gaps includes a gap code comprising: a block-skip code representing a number of bitmaps to skip, and a slot-skip code representing a number of bytes to skip within a bitmap.