COLUMNPROPERTY (Transact-SQL)
Returns information about a column or parameter.
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Transact-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
Note
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.
StatisticalSemantics
Column is enabled for semantic indexing.
1 = TRUE
0 = FALSE
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 Use Sparse Columns.
1= TRUE
0= FALSE
NULL = Input is not valid.
IsColumnSet
Column is a column set. For more information, see Use 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.
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.
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 AdventureWorks2012;
GO
SELECT COLUMNPROPERTY( OBJECT_ID('Person.Person'),'LastName','PRECISION')AS 'Column Length';
GO
Here is the result set.
Column Length
-------------
50