Abstract: A grouping mechanism is provided which can return distinct groups of entries of data that satisfy a users query in a non-blocking fashion. Each distinct group can normaly be returned to the user substantially concurrently with the following entries being received and processed. The grouping mechanism supports an overflow mechanism which can transfer parts of the data between a primary memory to a secondary memory to alleviate shortage of primary memory. This non-blocking mechanism is useful as a part of a dataflow model data processing system.

Abstract: A grouping mechanism is provided which can return distinct groups of entries of data that satisfy a users query in a non-blocking fashion. Each distinct group can normaly be returned to the user substantially concurrently with the following entries being received and processed. The grouping mechanism supports an overflow mechanism which can transfer parts of the data between a primary memory to a secondary memory to alleviate shortage of primary memory. This non-blocking mechanism is useful as a part of a dataflow model data processing system.

Abstract: A method for executing after-triggers in an active database. A tree is constructed for each after-trigger and an operator tree is constructed for the statement that activates the trigger. The method joins each of the trees for the activated row-after triggers to the operator tree for pipelined execution with the operator tree. The trees for the activated row-after triggers form a group and each of the trees within the group execute in parallel with each other. The method joins trees for activated statement-after triggers to the operator tree for execution subsequent to the execution of the operator tree, the statement after trigger trees receiving rows from a temporary table that accumulates affected rows from the operator tree. Trees for activated statement after triggers form a group and each of the trees within the group execute in parallel with each other.

Abstract: A method for executing after-triggers in an active database. A tree is constructed for each after-trigger and an operator tree is constructed for the statement that activates the trigger. The method joins each of the trees for the activated row-after triggers to the operator tree for pipelined execution with the operator tree. The trees for the activated row-after triggers form a group and each of the trees within the group execute in parallel with each other. The method joins trees for activated statement-after triggers to the operator tree for execution subsequent to the execution of the operator tree, the statement after trigger trees receiving rows from a temporary table that accumulates affected rows from the operator tree. Trees for activated statement after triggers form a group and each of the trees within the group execute in parallel with each other.

Abstract: A method for executing after-triggers in an active database. A tree is constructed for each after-trigger and an operator tree is constructed for the statement that activates the trigger. The method joins each of the trees for the activated row-after triggers to the operator tree for pipelined execution with the operator tree. The trees for the activated row-after triggers form a group and each of the trees within the group execute in parallel with each other. The method joins trees for activated statement-after triggers to the operator tree for execution subsequent to the execution of the operator tree, the statement after trigger trees receiving rows from a temporary table that accumulates affected rows from the operator tree. Trees for activated statement after triggers form a group and each of the trees within the group execute in parallel with each other.