MDX Data Definition - CREATE SET

Artikkeli
02/28/2023

Creates a named set with session scope for the current cube.

Syntax

  
CREATE [SESSION] [ STATIC | DYNAMIC ] [HIDDEN] SET   
   CURRENTCUBE | Cube_Name  
      .Set_Name AS 'Set_Expression'  
      [,Property_Name = Property_Value, ...n]

Arguments

Cube_Name
A valid string expression that provides the name of the cube.

Set_Name
A valid string expression that provides the name for the named set being created.

Set_Expression
A valid Multidimensional Expressions (MDX) expression that returns a set.

Property_Name
A valid string that provides the name of a set property.

Property_Value
A valid scalar expression that defines the set property's value.

Remarks

A named set is a set of dimension members (or an expression that defines a set) that you create to use again. For example, a named set makes it possible to define a set of dimension members that consists of the set of the top ten stores by sales. This set can be defined statically, or by means of a function like TopCount. This named set can then be used wherever the set of the top 10 stores is needed.

The CREATE SET statement creates a named set that remains available throughout the session, and therefore, can be used in multiple queries in a session. For more information, see Creating Session-Scoped Calculated Members (MDX).

You can also define a named set for use by a single query. To define such a set, you use the WITH clause in the SELECT statement. For more information about the WITH clause, see Creating Query-Scoped Named Sets (MDX).

The Set_Expression clause can contain any function that supports MDX syntax. Sets created with the CREATE SET statement that do not specify the SESSION clause have session scope. Use the WITH clause to create a set with query scope.

Specifying a cube other than the cube that is currently connected causes an error. Therefore, you should use CURRENTCUBE in place of a cube name to denote the current cube.

Scope

A user-defined set can occur within one of the scopes listed in the following table.

Query scope
The visibility and lifetime of the set is limited to the query. The set is defined in an individual query. Query scope overrides session scope. For more information, see Creating Query-Scoped Named Sets (MDX).

Session scope
The visibility and lifetime of the set is limited to the session in which it is created. (The lifetime is less than the session duration if a DROP SET statement is issued on the set.) The CREATE SET statement creates a set with session scope. Use the WITH clause to create a set with query scope.

Example

The following example creates a set called Core Products. The SELECT query then demonstrates calling the newly created set. The CREATE SET statement must be executed before the SELECT query can be executed - they cannot be executed in the same batch.

CREATE SET [Adventure Works].[Core Products] AS '{[Product].[Category].[Bikes]}'  
  
SELECT [Core Products] ON 0  
  FROM [Adventure Works]

Set Evaluation

Set evaluation can be defined to occur differently; it can be defined to occur only once at set creation or can be defined to occur every time the set is used.

STATIC
Indicates that the set is evaluated only once at the time the CREATE SET statement is evaluated.

DYNAMIC
Indicates that the set is to be evaluated every time it is used in a query.

Set Visibility

The set can be either visible or not to other users who query the cube.

HIDDEN
Specifies that the set is not visible to users who query the cube.

Standard Properties

Each set has a set of default properties. When a client application is connected to Analysis Services, the default properties are either supported, or available to be supported, as the administrator chooses.

Property identifier	Meaning
CAPTION	A string that the client application uses as the caption for the set.
DISPLAY_FOLDER	A string that identifies the path of the display folder that the client application uses to show the set. The folder level separator is defined by the client application. For the tools and clients supplied by Analysis Services, the backslash (\) is the level separator. To provide multiple display folders for a defined set, use a semicolon (;) to separate the folders.

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