Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
91 words
A method for encoding a signature, representing and providing at least partial accessibility, in a database processing system, to a record having two or more data items, the method comprising the steps of: (a) computing a base signature representing at least two of the record's data items; (b) initialising a combinatorial signature having more bits than the base signature; and (c) assigning values to bits of the combinatorial signature based on one or more logical operations on the bits of respective sets of two or more bits of the base signature.
Claim 2
Independent Claim
91 words
A method for encoding a signature, representing and providing at least partial accessibility, in a database processing system, to a record having two or more data items, the method comprising the steps of: (a) computing a base signature representing at least two of the record's data items; (b) initialising a combinatorial signature having more bits than the base signature; and (c) assigning values to bits of the combinatorial signature based on one or more logical operations on the bits of respective sets of two or more bits of the base signature.
Claim 3
Dependent Claim
29 words
A method as claimed in claim 1, wherein the base signature is computed by hashing the two or more data items of the record represented by the base signature.
Claim 4
Independent Claim
26 words
A method as claimed in either preceding claim, wherein step (c) assigns values based on the logical intersection (AND) of the bits of the respective sets.
Claim 5
Independent Claim
79 words
A method as claimed in any preceding claim, further including the steps of: (d) repeating steps (a) and (c) to compute a second combinatorial signature for a second record; (e) initialising a second-level combinatorial signature having at least the same number of bits as the first and second combinatorial signatures; and (f) assigning values to bits of the second level combinatorial signature based on one or more logical operations on corresponding bits of the first and second combinatorial signatures.
Claim 6
Dependent Claim
41 words
A method as claimed in claim 2, wherein step (b) zeroes the combinatorial signature; and step (c) sets each bit of the combinatorial signature equal to one only if all of the bits of the respective set are equal to one.
Claim 7
Dependent Claim
72 words
A method as claimed in claim 4, wherein step (b) zeroes both the first and second combinatorial signatures; step (c) sets each bit of the combinatorial signature equal to one only if all of the bits of the respective set are equal to one; and step (f) sets each bit of the second-level combinatorial signature equal to the logical union (OR) of the corresponding bits of the first and second combinatorial signatures.
Claim 8
Dependent Claim
61 words
A database management system arranged, inter alia, to maintain an index including leaf pages having pointers to respective data pages of records, the index including a second-level combinatorial signature encoded as claimed in claim 4 or claim 6 representing the records of a data page, the signature being stored in the data page's respective lowest level non-leaf page of the index.
Claim 9
Dependent Claim
36 words
A database management system as claimed in claim 7, wherein searching the index includes rejecting data pages whose respective second-level combinatorial signatures indicate that no records of such data pages match the criteria of the search.