Scan sharing for query predicate evaluations in column-based in-memory database systems

A computer program product comprising a computer readable storage medium having computer readable program code embodied therewith, said computer readable program code comprising:

• computer readable program code configured to obtain a plurality of queries of an in-memory column-oriented database, each of said queries having at least one column predicate;
• computer readable program code configured to determine, for each of said queries, which of a plurality of columns in said in-memory column-oriented database need to be scanned;
• computer readable program code configured to group said plurality of queries into a plurality of scan groups, based at least in part on said determining step;
• and
• computer readable program code configured to evaluate said column predicates for those of said queries in a given one of said scan groups in accordance with a scheduling scheme;
• wherein said grouping and said scheduling scheme take into account real time scan information.

An apparatus comprising:

• a memory;
• and
• at least one processor, coupled to said memory, and operative to:
• obtain a plurality of queries of an in-memory column-oriented database, each of said queries having at least one column predicate;
• determine, for each of said queries, which of a plurality of columns in said in-memory column-oriented database need to be scanned;
• group said plurality of queries into a plurality of scan groups, based at least in part on said determining;
• and
• evaluate said column predicates for those of said queries in a given one of said scan groups in accordance with a scheduling scheme;
• wherein said grouping and said scheduling scheme take into account real time scan information.

An apparatus comprising:

• means for obtaining a plurality of queries of an in-memory column-oriented database, each of said queries having at least one column predicate;
• means for determining, for each of said queries, which of a plurality of columns in said in-memory column-oriented database need to be scanned;
• means for grouping said plurality of queries into a plurality of scan groups, based at least in part on said determining step;
• and
• means for evaluating said column predicates for those of said queries in a given one of said scan groups in accordance with a scheduling scheme;
• wherein said means for grouping and said scheduling scheme take into account real time scan information.