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SqlFacetAttribute Class

Definition

Annotates the returned result of a user-defined type (UDT) with additional information that can be used in Transact-SQL.

public ref class SqlFacetAttribute : Attribute
[System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter | System.AttributeTargets.Property | System.AttributeTargets.ReturnValue, AllowMultiple=false, Inherited=false)]
public class SqlFacetAttribute : Attribute
[<System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter | System.AttributeTargets.Property | System.AttributeTargets.ReturnValue, AllowMultiple=false, Inherited=false)>]
type SqlFacetAttribute = class
    inherit Attribute
Public Class SqlFacetAttribute
Inherits Attribute
Inheritance
SqlFacetAttribute
Attributes

Remarks

SqlFacetAttribute may only be specified on non-void return values.

SqlFacetAttribute is used only to derive information about the return type, and is not intended to be a constraint specification on what can be stored in the type. Thus, if a field has a SqlFacetAttribute indicating its size to be 2 characters, then the SQL Server type of the field access expression is of size 2, but assignments into the field are not restricted by this facet.

The table below captures the matrix of valid values for the various properties for specific field types. In this table, "Y" indicates that the property is valid, and "N" indicates that the property is not valid.

The specified SqlFacetAttribute must be compatible with the field type. If the property is not valid, type registration will report an error if the user specifies a non-default value for the property. The maximum values for Precision and Scale properties are 38. For the MaxSize property, the value should be in the range of 1-8000 for binary and non-Unicode data, 1-4000 for Unicode data, or -1. All other values are not valid.

Type IsFixedLength MaxSize Precision Scale IsNullable
SqlBoolean N N N N Y
SqlByte N N N N Y
SqlInt16 N N N N Y
SqlInt32 N N N N Y
SqlInt64 N N N N Y
SqlSingle N N N N Y
SqlDouble N N N N Y
SqlDateTime N N N N Y
SqlMoney N N N N Y
SqlGuid N N N N Y
SqlDecimal N N Y Y Y
SqlString Y Y N N Y
SqlBinary Y Y N N Y
SqlXml N N N N Y
SqlBytes Y Y N N Y
SqlChars Y Y N N Y
Embedded UDTs N N N N Y
String Y Y N N Y
Byte[] Y Y N N Y
Char[] Y Y N N Y
DateTime N N N Y1 N
Decimal N N Y Y Y

(1) Specifying the scale on a DateTime type will cause the value to be returned to Transact-SQL as a DateTime2 type with the specified scale.

Constructors

SqlFacetAttribute()

An optional attribute on a user-defined type (UDT) return type, used to annotate the returned result with additional information that can be used in Transact-SQL.

Properties

IsFixedLength

Indicates whether the return type of the user-defined type is of a fixed length.

IsNullable

Indicates whether the return type of the user-defined type can be null.

MaxSize

The maximum size, in logical units, of the underlying field type of the user-defined type.

Precision

The precision of the return type of the user-defined type.

Scale

The scale of the return type of the user-defined type.

Applies to