Compression aware aggregations for queries with expressions

A computer-implemented method, comprising:

• executing a relational database management system (RDBMS) in a computer system, wherein:
• the RDBMS manages a relational database comprising a data storage facility, and at least one column-partitioned base table within said data storage facility storing data;
• receiving, by said RDBMS, an aggregation query for execution by said RDBMS, said query containing a GROUP-BY clause containing references to multiple fields within said table;
• generating, by said RDBMS, executable code for said query, said executable code including an executable code chunk for evaluating said GROUP-BY clause, and an executable code chunk for performing aggregation;
• executing, by said RDBMS, said executable code chunk for evaluating said GROUP-BY clause to generate a hash for said multiple grouping fields, and using said hash to generate an intermediate, partially aggregated result set;
• and
• executing, within said data storage facility using push-down aggregation techniques, said executable code chunk for performing aggregation on the intermediate, partially aggregated result set to generate a final result for said query.

A computer-implemented method, comprising:

• executing a relational database management system (RDBMS) in a computer system, wherein:
• the RDBMS manages a relational database comprising a data storage facility, and at least one column-partitioned base table within said data storage facility storing data;
• receiving, by said RDBMS, an aggregation query for execution by said RDBMS, said query containing a GROUP-BY clause containing an expression involving multiple fields within said table;
• generating, by said RDBMS, executable code for said query, said executable code including an executable code chunk for evaluating said expression, and an executable code chunk for performing aggregation;
• executing, by said RDBMS, said executable code chunk for evaluating said expression to generate a set of GROUP-BY values, and using said set of GROUP-BY values to generate an intermediate, partially aggregated result set;
• and
• executing, within said data storage facility using push-down aggregation techniques, said executable code chunk for performing aggregation on the intermediate, partially aggregated result set to generate a final result for said query.

A computer-implemented method, comprising:

• executing a relational database management system (RDBMS) in a computer system, wherein:
• the RDBMS manages a relational database comprising a data storage facility, and at least one column-partitioned base table within said data storage facility storing data;
• receiving, by said RDBMS, an aggregation query for execution by said RDBMS, said query containing at least one SELECT statement referencing column values within a compressed column within said table;
• generating, by said RDBMS, executable code for said query, said executable code including an executable code chunk for evaluating said compressed values from said compressed column, and an executable code chunk for performing aggregation;
• executing said executable code chunk for evaluating said compressed values from said compressed column to generate an intermediate, partially aggregated result set;
• and
• executing, within said data storage facility using push-down aggregation techniques, said executable code chunk for performing aggregation on the intermediate, partially aggregated result set and generate a final result for said aggregation.