Augmented query optimization by data flow graph model optimizer

A computer program product comprising a non-transitory machine-readable medium storing instructions that, when executed by at least one programmable processor, cause the at least one programmable processor to perform operations comprising:

• receiving a query;
• generating, at a calculation engine and in response to the query, a calculation scenario for executing the query on a database, the calculation scenario comprising an initial data flow graph comprising data flows between a database server and an application server and a plurality of nodes representing operations for executing the query, at least one node of the plurality of nodes comprising a set of inputs and outputs and at least one operation that transforms the inputs into the outputs;
• optimizing the initial data flow graph into an optimized data flow graph, the optimizing comprising:
• enriching, by a model optimizer, the initial data flow graph with a hint on one or more nodes of the plurality of nodes to provide instructions indicating an optimization to be performed at one or more unoptimized nodes within the dataflow graph hierarchy;
• applying, by a rules engine of the model optimizer, a set of rules to the initial data flow graph, the set of rules comprising a first rule, the first rule defining a first optimization to the initial data flow graph and how and when to apply the first optimization;
• determining, by the model optimizer, that the first rule comprises a disqualification fact that would prevent the first optimization from being completed by the model optimizer according to the first rule;
• applying, by the model optimizer and based on the determining, the hint to override the disqualification fact of the first rule such that the first optimization is applied differently than indicated by the first rule;
• applying, by the model optimizer and in response to the applying the hint, remaining rules of the set of rules to the initial data flow graph to create the optimized data flow graph;
• and
• initiating execution of the query on the database using the optimized data flow graph such that a hierarchy of nodes in the data flow graph, that would have remained unoptimized if the hint was not applied to override the disqualification fact of the first rule, are optimized based on a determination of whether the hint was applied.

A system comprising:

• one or more data processors;
• and
• memory storing instructions, which when executed, cause one or more of the at least one data processor to perform operations comprising:
• receiving a query;
• generating, at a calculation engine and in response to the query, a calculation scenario for executing the query on a database, the calculation scenario comprising an initial data flow graph comprising data flows between a database server and an application server and a plurality of nodes representing operations for executing the query, at least one node of the plurality of nodes comprising a set of inputs and outputs and at least one operation that transforms the inputs into the outputs;
• optimizing the initial data flow graph into an optimized data flow graph, the optimizing comprising:
• enriching, by a model optimizer, the initial data flow graph with a hint on one or more nodes of the plurality of nodes to provide instructions indicating an optimization to be performed at one or more unoptimized nodes within the dataflow graph hierarchy;
• applying, by a rules engine of the model optimizer, a set of rules to the initial data flow graph, the set of rules comprising a first rule, the first rule defining a first optimization to the initial data flow graph and how and when to apply the first optimization;
• determining, by the model optimizer, that the first rule comprises a disqualification fact that would prevent the first optimization from being completed by the model optimizer according to the first rule;
• applying, by the model optimizer and based on the determining, the hint to override the disqualification fact of the first rule such that the first optimization is applied differently than indicated by the first rule;
• applying, by the model optimizer and in response to the applying the hint, remaining rules of the set of rules to the initial data flow graph to create the optimized data flow graph;
• and
• initiating execution of the query on the database using the optimized data flow graph such that a hierarchy of nodes in the data flow graph, that would have remained unoptimized if the hint was not applied to override the disqualification fact of the first rule, are optimized based on a determination of whether the hint was applied.