Calculation scenarios with semantic nodes

摘要

A calculation engine is described that executes calculation scenarios comprising a plurality of calculation nodes that each specify operations to be performed to execute the query. One of the nodes can be a semantic node that is used to modify the query for operations requiring special handling. Related apparatus, systems, methods, and articles are also described.

主权项

1. A method comprising:
receiving, by a database server from a remote application server, a query associated with a calculation scenario that defines a data flow model that includes a plurality of calculation nodes, each calculation node defining one or more operations to execute on the database server, at least one of the nodes being a semantic node specifying an operation requiring special handling; modifying, by the database server, the query using the semantic node; modifying, by the database server, the calculation scenario based on the modified query; instantiating, by the database server, the modified calculation scenario; executing, by the database server, the operations defined by the calculation nodes of the modified calculation scenario to result in at least one result set; and providing, by the database server to the application server, the at least one result set; wherein the received query specifies an aggregation function on a calculated attribute, and wherein the special handling specified by the semantic node overrides the aggregation function on the calculated attribute to a projection operation.