System.Data.SqlTypes Namespace

http://msdn2.microsoft.com/en-us/library/system.data.sqltypes.aspx

The System.Data.SqlTypes namespace provides classes for native data types within SQL Server 2005. These classes provide a safer, faster alternative to the data types provided by the .NET Framework common language runtime (CLR). Using the classes in this namespace helps prevent type conversion errors caused by loss of precision. Because other data types are converted to and from SqlTypes behind the scenes, explicitly creating and using objects within this namespace also yields faster code.

Each data type in SqlTypes has its equivalent data type in SQL Server 2005, with the same underlying data representation. Many of them also have equivalent data types in the CLR. However, SqlDateTime, SqlDecimal, and SqlString have different underlying data structures with their corresponding .NET Framework data types.

The following table maps the members of the SqlTypes namespace to Microsoft SQL Server data types and to the members of the SqlDbType enumeration.

.NET Framework SqlTypes	Native SQL Server	.NET Framework SqlDbType
SqlBinary	binary, image, timestamp, varbinary	Binary, Image, TimeStamp, VarBinary
SqlBoolean	bit	Bit
SqlByte	tinyint	TinyInt
SqlDateTime	datetime, smalldatetime	DateTime, SmallDateTime
SqlDecimal	decimal	Decimal
SqlDouble	float	Float
SqlGuid	uniqueidentifier	UniqueIdentifier
SqlInt16	smallint	SmallInt
SqlInt32	int	Int
SqlInt64	bigint	BigInt
SqlMoney	money, smallmoney	Money, SmallMoney
SqlSingle	real	Real
SqlString	char, nchar, text, ntext, nvarchar, varchar	Char, NChar, Text, Ntext, NVarChar, VarChar
SqlXml	xml	Xml

	Interface	Description
	INullable	All the System.Data.SqlTypes objects and structures implement the INullable interface.

	Structure	Description
	SqlBinary	Represents a variable-length stream of binary data to be stored in or retrieved from a database.
	SqlBoolean	Represents an integer value that is either 1 or 0 to be stored in or retrieved from a database.
	SqlByte	Represents an 8-bit unsigned integer, in the range of 0 through 255, to be stored in or retrieved from a database.
	SqlDateTime	Represents the date and time data ranging in value from January 1, 1753 to December 31, 9999 to an accuracy of 3.33 milliseconds to be stored in or retrieved from a database. The SqlDateTime structure has a different underlying data structure from its corresponding .NET Framework type, DateTime, which can represent any time between 12:00:00 AM 1/1/0001 and 11:59:59 PM 12/31/9999, to the accuracy of 100 nanoseconds. SqlDateTime actually stores the relative difference to 00:00:00 AM 1/1/1900. Therefore, a conversion from "00:00:00 AM 1/1/1900" to an integer will return 0.
	SqlDecimal	Represents a numeric value between - 10^38 +1 and 10^38 - 1, with fixed precision and scale.
	SqlDouble	Represents a floating-point number within the range of -1.79E +308 through 1.79E +308 to be stored in or retrieved from a database.
	SqlGuid	Represents a GUID to be stored in or retrieved from a database.
	SqlInt16	Represents a 16-bit signed integer to be stored in or retrieved from a database.
	SqlInt32	Represents a 32-bit signed integer to be stored in or retrieved from a database.
	SqlInt64	Represents a 64-bit signed integer to be stored in or retrieved from a database.
	SqlMoney	Represents a currency value ranging from -2 ⁶³ (or -922,337,203,685,477.5808) to 2 ⁶³ -1 (or +922,337,203,685,477.5807) with an accuracy to a ten-thousandth of currency unit to be stored in or retrieved from a database.
	SqlSingle	Represents a floating point number within the range of -3.40E +38 through 3.40E +38 to be stored in or retrieved from a database.
	SqlString	Represents a variable-length stream of characters to be stored in or retrieved from the database. SqlString has a different underlying data structure from its corresponding .NET Framework String data type. String always uses the default CultureInfo from the current thread, but SqlString contains its own locale Id and compare flags. The comparison result of two SqlString structures is independent of operating system and current thread locale.

	Class	Description
	SqlAlreadyFilledException	The SqlAlreadyFilledException class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	SqlBytes	Represents a mutable reference type that wraps either a Buffer or a Stream.
	SqlChars	SqlChars is a mutable reference type that wraps a Char array or a SqlString instance.
	SqlNotFilledException	The SqlNotFilledException class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	SqlNullValueException	The exception that is thrown when the Value property of a System.Data.SqlTypes structure is set to null.
	SqlTruncateException	The exception that is thrown when you set a value into a System.Data.SqlTypes structure would truncate that value.
	SqlTypeException	The base exception class for the System.Data.SqlTypes.
	SqlTypesSchemaImporterExtensionHelper	The SqlTypesSchemaImporterExtensionHelper class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	SqlXml	Represents XML data stored in or retrieved from a server.
	TypeBigIntSchemaImporterExtension	The TypeBigIntSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeBinarySchemaImporterExtension	The TypeBinarySchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeBitSchemaImporterExtension	The TypeBitSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeCharSchemaImporterExtension	The TypeCharSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeDateTimeSchemaImporterExtension	The TypeDateTimeSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeDecimalSchemaImporterExtension	The TypeDecimalSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeFloatSchemaImporterExtension	The TypeFloatSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeIntSchemaImporterExtension	The TypeIntSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeMoneySchemaImporterExtension	The TypeMoneySchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeNCharSchemaImporterExtension	The TypeNCharSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeNTextSchemaImporterExtension	The TypeNTextSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeNumericSchemaImporterExtension	The TypeNumericSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeNVarCharSchemaImporterExtension	The TypeNVarCharSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeRealSchemaImporterExtension	The TypeRealSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeSmallDateTimeSchemaImporterExtension	The TypeSmallDateTimeSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeSmallIntSchemaImporterExtension	The TypeSmallIntSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeSmallMoneySchemaImporterExtension	The TypeSmallMoneySchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeTextSchemaImporterExtension	The TypeTextSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeTinyIntSchemaImporterExtension	The TypeTinyIntSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeUniqueIdentifierSchemaImporterExtension	The TypeUniqueIdentifierSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeVarBinarySchemaImporterExtension	The TypeVarBinarySchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeVarCharSchemaImporterExtension	The TypeVarCharSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.
	TypeVarImageSchemaImporterExtension	The TypeVarImageSchemaImporterExtension class is not intended for use as a stand-alone component, but as a class from which other classes derive standard functionality.