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Level Interface

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  Diese Funktion wird in der nächsten Version von Microsoft SQL Server entfernt. Verwenden Sie diese Funktion beim Entwickeln neuer Anwendungen nicht, und planen Sie so bald wie möglich das Ändern von Anwendungen, in denen es zurzeit verwendet wird.

Levels describe the hierarchy within a dimension from the highest (most precalculated) to the lowest (most detailed) levels of data.

The following table shows an example of level positions of a time dimension in which the most detailed (day) values are included in the next level (week), which are, in turn, included in the next level (quarter), and so on. If the Year level has 4 members, 1994 through 1997, then the Quarter level has 4 members for each year, and the Week level has 52 members for each year.

Level

Position in hierarchy

Year

1

Quarter

2

Week

3

Day

4

In Decision Support Objects (DSO), objects that implement the Level interface have one of the following ClassType property values.

ClassType

Description

clsAggregationLevel

The levels contained within an aggregation dimension objects levels collection

clsCubeLevel

The levels of all dimensions assigned to a cube

clsDatabaseLevel

The levels of all dimensions within a database

clsPartitionLevel

The levels of all of the dimensions contained within a partition

Additionally, the SubClassType property for level objects can have the following values.

Subclass type

Description

sbclsRegular

A regular level

sbclsParentChild

A parent-child level

The Level interface provides a number of properties to manipulate these objects. For more information about levels and other objects, see Introducing Decision Support Objects.

Differences in the implementation of the Level interface exist between the derived objects. Some objects provide read-only access to a few Level properties, while others implement a subset of the properties contained in the interface. For example, a clsDatabaseLevel object allows read and write access to its LevelType property, whereas, for a clsPartitionLevel object, access to this property is read-only. For more information about the Level interface properties and their applicability to the associated objects, see Collections, Level Interface and Properties, Level Interface.

There are no methods associated with the Level interface.

Parent-Child Levels

Parent-child levels appear only in parent-child dimensions (those whose SubClassType is sbclsParentChild). Unlike regular levels that are constructed using predefined member columns, parent-child levels function as templates for hierarchies that are dynamically built from source tables with parent-child relationships. Parent-child levels identify the MemberKeyColumn, MemberNameColumn, and ParentKeyColumn properties of the data source, which are used to dynamically build variable-level hierarchies.