IGQIOptimizableDataSource interface

Available from DataMiner 10.3.3/10.4.0 onwards.

Note

This interface is only used by the GQI framework in the lifecycle for ad hoc data sources from DataMiner 10.5.0 [CU2]/10.5.5 onwards when using the GQI DxM.

Definition

• Namespace: Skyline.DataMiner.Analytics.GenericInterface
• Assembly: SLAnalyticsTypes.dll

The IGQIOptimizableDataSource interface can be used to optimize an ad hoc data source based on operators added to a query.

Common optimizations include:

• Inspecting the properties of an operator to make data retrieval more efficient.
• Removing or replacing an operator to implement the same operation more efficiently in the ad hoc data source.

Important

Optimizing an operator should never change the functional behavior of the query. If an ad hoc data source removes or alters an operator, it is responsible for keeping the final result functionally equivalent.

Tip

You can implement this interface to forward sort operations to an underlying database to improve performance.

Methods

IGQIQueryNode Optimize(IGQIDataSourceNode currentNode, IGQICoreOperator nextOperator)

Called when an optimizable operator is appended directly to the ad hoc data source. Given the current query node that represents the ad hoc data source and the next operator, it should return the resulting query node.

Tip

Learn more about when this method is called within an ad hoc data source.

Important

• The Optimize method may not be called if there are no supported subsequent operators.
• The Optimize method will be called each time the next operator changes.

Note

Currently, the Optimize method only triggers for filter operators (IGQIFilterOperator) and (from DataMiner 10.4.0/10.4.1 onwards) sort operators (IGQISortOperator).

Parameters

• IGQIDataSourceNode currentNode: A reference to the current node.
• IGQICoreOperator nextOperator: A reference to the next operator.

Examples

Appending an operator (default behavior)

By appending an operator to a query node, you tell the GQI framework to apply the operation after that node.

To append an operator to a query node, you can call its Append(IGQICoreOperator) method. The following implementation has the same behavior as if the IGQIOptimizableDataSource interface was not implemented.

public IGQIOperatorNode Optimize(IGQIDataSourceNode currentNode, IGQICoreOperator nextOperator)
{
    return currentNode.Append(nextOperator);
}

Removing or replacing an operator

By not appending a given operator, you cause the operation to no longer be applied by the GQI framework. The ad hoc data source then becomes solely responsible for ensuring that the result remains equivalent.

This approach can be used to provide custom, more efficient implementations of operations like filtering and sorting.

public IGQIOperatorNode Optimize(IGQIDataSourceNode currentNode, IGQICoreOperator nextOperator)
{
    // Custom logic to try and optimize for the next operator
    if (TryOptimizeFor(nextOperator))
    {
        // Return our current node that is now also responsible for the operation
        return currentNode;
    }

    // Fall back to the default behavior
    return currentNode.Append(nextOperator);
}

See also

• The ad hoc data source lifecycle.
• The IGQIOptimizableOperator to optimize custom operators.
• Example: Optimizing filter operations.
• Example: Optimizing sort operations.