Dataset Object

OLE DB for OLAP defines an additional OLE DB object. The dataset object provides an abstraction for a multidimensional result set.

The following diagram shows the interfaces available on this object. Mandatory interfaces are shown on the right, and optional interfaces are shown on the left.

OLE DB for OLAP dataset objects are defined as follows:

CoType TDataset {
[mandatory]   interface IMDDataset;
[mandatory]   interface IAccessor;
[mandatory]   interface IConvertType;
[mandatory]   interface IColumnsInfo;
[optional]    interface IMDFind;
[optional]    interface IMDRangeRowset;
[optional]    interface ISupportErrorInfo;
}

The interfaces and methods perform the following actions:

• Give the number of axes and the contents of each axis.

• Provide information about the slicer dimensions (the tuple in the WHERE clause).

• Create an accessor.

• Describe values such as the number and data type of cell properties.

• Retrieve cell property values.

• Search the dataset for a given cell and search the axes for a given tuple.

• Provide information about supported data type conversions.

• Retrieve an interface on the command object that created the dataset object.

Where possible, the existing OLE DB infrastructure used for navigation, description, and other functions has been used for OLE DB for OLAP.