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SourceColumn (clsColumn)

Note

  This feature will be removed in the next version of Microsoft SQL Server. Do not use this feature in new development work, and modify applications that currently use this feature as soon as possible.

The SourceColumn property of an object of ClassType clsColumn identifies the name of its source column in a relational table. This property applies only to columns belonging to mining model objects of SubClassType sbclsRegular.

Data Type

String

Access

Read/write for columns with a SubClassType of sbclsRegular, read-only for all others.

Remarks

For columns with a SubClassType of sbclsNested that belong to a mining model object of SubClassType of sbclsRegular, this property returns an empty string.

To understand the function of this property, consider the relationships of columns in a model to an SQL query. If you use a SELECT query to define the structure of a table when you create a mining model, the contents of this property for each column in the model correspond to a column designation within the SELECT query. For example, consider the following query:

SELECT "Key" AS "CustId", "Age" AS "Age" FROM "People"

If a mining model were to be created using this SELECT statement, the SourceColumn properties for each column would be "Key" and "Age" respectively.

Examples

Creating a Data Mining Model

The following example creates a data mining model based upon the People table of a relational database. This table is specified by the FromClause property. Because the model is based upon a single table, no joins are needed. It then creates and adds two columns to the model's Columns collection. Each column is related to a field in the original relational table (that is to say, the People table) by setting the SourceColumn property of each column to the appropriate value.

dsoDmm.Description = "Analyzes the purchasing behavior of customers"
dsoDmm.MiningAlgorithm = "Microsoft_Decision_Trees"
dsoDmm.FromClause = "People"
dsoDmm.JoinClause = "" ' None is needed because there is only a single table.
dsoDmm.Filter = ""
dsoDmm.TrainingQuery = "" 'Let DSO figure out the training query.

Set dsoColumn = dsoDmm.Columns.AddNew("CustId")
dsoColumn.SourceColumn = "People.Key"
dsoColumn.DataType = adInteger
dsoColumn.IsKey = True

Set dsoColumn = dsoDmm.Columns.AddNew("Age")
dsoColumn.SourceColumn = "People.Age"
dsoColumn.DataType = adDouble
dsoColumn.ContentType = "CONTINUOUS"

See Also

Reference