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Column Element for Index (DTA)

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

Składnia

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

Element Attributes

Column Attribute

Description

Type

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

Allowed Value

Description

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)

Przykład

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

Zobacz także

Odwołanie

XML Input File Reference (Database Engine Tuning Advisor)