Patent attributes
method for querying a data storage includes receiving queries for execution in the data storage, and deriving from the queries one or more table-scans over one or more tables of the data storage. Candidate sparse indexes, for pruning the table-scans, are specified based on the queries. Pruning-power measures, indicative of as effectiveness of the candidate sparse indexes in pruning the table-scans, are evaluated. One or more of the candidate sparse indexes are converted into actual sparse indexes, depending on the pruning-power measures. The queries are executed by performing the table-scans, including pruning the table-scans using the actual sparse indexes.

