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Column Element for Index (DTA)

Applies to: SQL Server

Specifies the columns on which the index is created for a user-specified configuration.

Syntax

  
<Create>  
  <Index>  
    <Name>...</Name>  
    <Column [Type | SortOrder]>  
     ...code removed here...  
     </Column>  

Element Attributes

Type: Optional. Specifies the index column type. Use a string data type to specify this attribute with one of the following allowed values:

  • KeyColumn

    Specifies that the column is referenced by an index key. Use the following syntax to set this attribute:

    <Column Type="KeyColumn">  
    

    For more information about key columns, see Clustered and Nonclustered Indexes Described.

  • IncludedColumn

    Specifies that the column is an included column (instead of a key column). Use the following syntax to set this attribute:

    <Column Type="IncludedColumn">  
    

    For more information about included columns, see Create Indexes with Included Columns.

SortOrder: Optional. Specifies the sorting order of the column. Use a string data type to specify either an "Ascending" or "Descending" sorting order as follows:

<Column SortOrder="Ascending">  

Element Characteristics

Characteristic Description
Data type and length None.
Default value None.
Occurrence Can specify up to 1024 columns for the Index element.

Element Relationships

Relationship Elements
Parent element Index Element (DTA)
Child elements Name Element for Column (DTA)

Example

For a usage example of this element, see the XML Input File Sample with User-specified Configuration (DTA).

See Also

XML Input File Reference (Database Engine Tuning Advisor)