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COLUMNPROPERTY (Transact-SQL)

Returns information about a column or parameter.

Topic link iconTransact-SQL Syntax Conventions

Syntax

COLUMNPROPERTY (id ,column ,property )

Arguments

  • id
    Is an expression that contains the identifier (ID) of the table or procedure.

  • column
    Is an expression that contains the name of the column or parameter.

  • property
    Is an expression that contains the information to be returned for id, and can be any one of the following values.

    Value

    Description

    Value returned

    AllowsNull

    Allows null values.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    ColumnId

    Column ID value corresponding to sys.columns.column_id.

    Column ID

    NoteNote
    When querying multiple columns, gaps may appear in the sequence of Column ID values.

    FullTextTypeColumn

    The TYPE COLUMN in the table that holds the document type information of the column.

    ID of the full-text TYPE COLUMN for the column passed as the second parameter of this property.

    IsComputed

    Column is a computed column.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    IsCursorType

    Procedure parameter is of type CURSOR.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    IsDeterministic

    Column is deterministic. This property applies only to computed columns and view columns.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid. Not a computed column or view column.

    IsFulltextIndexed

    Column has been registered for full-text indexing.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    IsIdentity

    Column uses the IDENTITY property.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    IsIdNotForRepl

    Column checks for the IDENTITY_INSERT setting.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    IsIndexable

    Column can be indexed.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    IsOutParam

    Procedure parameter is an output parameter.

    1 = TRUE

    0 = FALSE NULL = Input is not valid.

    IsPrecise

    Column is precise. This property applies only to deterministic columns.

    1 = TRUE

    0 = FALSE NULL = Input is not valid. Not a deterministic column

    IsRowGuidCol

    Column has the uniqueidentifier data type and is defined with the ROWGUIDCOL property.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    IsSystemVerified

    The determinism and precision properties of the column can be verified by the Database Engine. This property applies only to computed columns and columns of views.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    IsXmlIndexable

    The XML column can be used in an XML index.

    1 = TRUE

    0 = FALSE

    NULL = Input is not valid.

    Precision

    Length for the data type of the column or parameter.

    The length of the specified column data type

    -1 = xml or large value types

    NULL = Input is not valid.

    Scale

    Scale for the data type of the column or parameter.

    The scale

    NULL = Input is not valid.

    SystemDataAccess

    Column is derived from a function that accesses data in the system catalogs or virtual system tables of SQL Server. This property applies only to computed columns and columns of views.

    1 = TRUE (Indicates read-only access.)

    0 = FALSE

    NULL = Input is not valid.

    UserDataAccess

    Column is derived from a function that accesses data in user tables, including views and temporary tables, stored in the local instance of SQL Server. This property applies only to computed columns and columns of views.

    1 = TRUE (Indicates read-only access.)

    0 = FALSE

    NULL = Input is not valid.

    UsesAnsiTrim

    ANSI_PADDING was set ON when the table was first created. This property applies only to columns or parameters of type char or varchar.

    1= TRUE

    0= FALSE

    NULL = Input is not valid.

    IsSparse

    Column is a sparse column. For more information, see Using Sparse Columns.

    1= TRUE

    0= FALSE

    NULL = Input is not valid.

    IsColumnSet

    Column is a column set. For more information, see Using Column Sets.

    1= TRUE

    0= FALSE

    NULL = Input is not valid.

Return Types

int

Exceptions

Returns NULL on error or if a caller does not have permission to view the object.

In SQL Server 2008, a user can only view the metadata of securables that the user owns or on which the user has been granted permission. This means that metadata-emitting, built-in functions such as COLUMNPROPERTY may return NULL if the user does not have any permission on the object. For more information, see Metadata Visibility Configuration and Troubleshooting Metadata Visibility.

Remarks

When you check the deterministic property of a column, first test whether the column is a computed column. IsDeterministic returns NULL for noncomputed columns. Computed columns can be specified as index columns.

Examples

The following example returns the length of the LastName column.

USE AdventureWorks2008R2;
GO
SELECT COLUMNPROPERTY( OBJECT_ID('Person.Person'),'LastName','PRECISION')AS 'Column Length';
GO

Here is the result set.

Column Length 
------------- 
50

(1 row(s) affected)