DYNAMIC DATA DISTRIBUTION AGGREGATION
Systems and methods reduce a time to calculate an aggregate of data values associated with a range of index entries. The system manages aggregate values within data stored in the entries of an index during insertion, modification, and deletion operations, and provides new index operations to generate aggregate values associated with a range of index entries. Multiple simultaneous operations can be executed efficiently.
1 . A method of returning information from a database search comprising:
creating an index list with positional counters in nodes for a first subindex;
maintaining for each entry an aggregate value of information in a second subindex for entries before each entry;
traversing the index list and obtaining a first aggregate value for all entries before a first value of the first subindex;
traversing the index list and obtaining a second aggregate value for a first entry after the first value of the first subindex;
subtracting the first aggregate value from the second aggregate value to identify the aggregate of the second subindex for entries with the same value in the first subindex;
returning to the user a response based on the subtracting.
2 . The method of claim 1 , wherein the aggregate value is a sum of values in the second subindex.
3 . The method of claim 2 , further comprising determining the number of items with the first value, and using the aggregate sum and number of items to determine an average.
4 . The method of claim 1 , wherein the aggregate value is a sum of squares of values in the second subindex.
5 . The method of claim 1 , wherein the index information is maintained in a B*tree index.
6 . A database system for implementing the method of claim 1 .
7 . The database of claim 6 , wherein the aggregate value is a sum of values in the second subindex.
8 . The database of claim 7 , further comprising determining the number of items with the first value, and using the aggregate sum and number of items to determine an average.
9 . The database of claim 6 , wherein the aggregate value is a sum of squares of values in the second subindex.
10 . The database of claim 6 , wherein the index information is maintained in a B*tree index.