CLR Datatype Mapping tables

SQL CLR Data type mapping

SQL Server data type	CLR data type (SQL Server)	CLR data type (.NET Framework)
bigint	SqlInt64	Int64, Nullable<Int64>
binary	SqlBytes, SqlBinary	Byte[]
bit	SqlBoolean	Boolean, Nullable<Boolean>
char	None	None
cursor	None	None
date	SqlDateTime	DateTime, Nullable<DateTime>
datetime	SqlDateTime	DateTime, Nullable<DateTime>
datetime2	SqlDateTime	DateTime, Nullable<DateTime>
DATETIMEOFFSET	None	DateTimeOffset, Nullable<DateTimeOffset>
decimal	SqlDecimal	Decimal, Nullable<Decimal>
float	SqlDouble	Double, Nullable<Double>
geography	SqlGeography defined in Microsoft.SqlServer.Types.dll Download here:feature pack.	None
geometry	SqlGeometry defined in Microsoft.SqlServer.Types.dll Download here: feature pack.	None
hierarchyid	SqlHierarchyId defined in Microsoft.SqlServer.Types.dll Download here: feature pack.	None
image	None	None
int	SqlInt32	Int32, Nullable<Int32>
money	SqlMoney	Decimal, Nullable<Decimal>
nchar	SqlChars, SqlString	String, Char[]
ntext	None	None
numeric	SqlDecimal	Decimal, Nullable<Decimal>
nvarchar	SqlChars, SqlString SQLChars is a better match for data transfer and access, and SQLString is a better match for performing String operations.	String, Char[]
nvarchar(1), nchar(1)	SqlChars, SqlString	Char, String, Char[], Nullable<char>
real	SqlSingle	Single, Nullable<Single>
rowversion	None	Byte[]
smallint	SqlInt16	Int16, Nullable<Int16>
smallmoney	SqlMoney	Decimal, Nullable<Decimal>
sql_variant	None	Object
table	None	None
text	None	None
time	TimeSpan	TimeSpan, Nullable<TimeSpan>
timestamp	None	None
tinyint	SqlByte	Byte, Nullable<Byte>
uniqueidentifier	SqlGuid	Guid, Nullable<Guid>
User-defined type(UDT)	None	The same class that is bound to the user-defined type in the same assembly or a dependent assembly.
varbinary	SqlBytes, SqlBinary	Byte[]
varbinary(1), binary(1)	SqlBytes, SqlBinary	byte, Byte[], Nullable<byte>
varchar	None	None
xml	SqlXml	None

Source: http://msdn.microsoft.com/en-us/library/ms131092.aspx




Image Source: http://msdn.microsoft.com/en-us/library/bb386947.aspx

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Platform Invoke Data Types

Unmanaged type in Wtypes.h	Unmanaged C language type	Managed class name	Description
HANDLE	void*	System.IntPtr	32 bits
BYTE	unsigned char	System.Byte	8 bits
SHORT	short	System.Int16	16 bits
WORD	unsigned short	System.UInt16	16 bits
INT	int	System.Int32	32 bits
UINT	unsigned int	System.UInt32	32 bits
LONG	long	System.Int32	32 bits
BOOL	long	System.Int32	32 bits
DWORD	unsigned long	System.UInt32	32 bits
ULONG	unsigned long	System.UInt32	32 bits
CHAR	char	System.Char	Decorate with ANSI.
LPSTR	char*	System.String or System.StringBuilder	Decorate with ANSI.
LPCSTR	Const char*	System.String or System.StringBuilder	Decorate with ANSI.
LPWSTR	wchar_t*	System.String or System.StringBuilder	Decorate with Unicode.
LPCWSTR	Const wchar_t*	System.String or System.StringBuilder	Decorate with Unicode.
FLOAT	Float	System.Single	32 bits
DOUBLE	Double	System.Double	64 bits

Source: http://msdn.microsoft.com/en-us/library/aa720411(VS.71).aspx

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Multiple Data Types Mapping Table

Category	Class name	Description	Visual Basic data type	C# data type	Managed Extensions for C++ data type	JScript data type
Integer	Byte	An 8-bit unsigned integer.	Byte	byte	char	Byte
	SByte	An 8-bit signed integer.Not CLS-compliant.	SByte No built-in type.	sbyte	signed char	SByte
	Int16	A 16-bit signed integer.	Short	short	short	short
	Int32	A 32-bit signed integer.	Integer	int	int -or- long	int
	Int64	A 64-bit signed integer.	Long	long	__int64	long
	UInt16	A 16-bit unsigned integer.Not CLS-compliant.	UInt16 No built-in type.	ushort	unsigned short	UInt16
	UInt32	A 32-bit unsigned integer.Not CLS-compliant.	UInt32 No built-in type.	uint	unsigned int -or- unsigned long	UInt32
	UInt64	A 64-bit unsigned integer.Not CLS-compliant.	UInt64 No built-in type.	ulong	unsigned __int64	UInt64
Floating point	Single	A single-precision (32-bit) floating-point number.	Single	float	float	float
	Double	A double-precision (64-bit) floating-point number.	Double	double	double	double
Logical	Boolean	A Boolean value (true or false).	Boolean	bool	bool	bool
Other	Char	A Unicode (16-bit) character.	Char	char	wchar_t	char
	Decimal	A 96-bit decimal value.	Decimal	decimal	Decimal	Decimal
	IntPtr	A signed integer whose size depends on the underlying platform (a 32-bit value on a 32-bit platform and a 64-bit value on a 64-bit platform).	IntPtr No built-in type.	IntPtr No built-in type.	IntPtr No built-in type.	IntPtr
	UIntPtr	An unsigned integer whose size depends on the underlying platform (a 32- bit value on a 32-bit platform and a 64-bit value on a 64-bit platform).Not CLS-compliant.	UIntPtr No built-in type.	UIntPtr No built-in type.	UIntPtr No built-in type.	UIntPtr
Class objects	Object	The root of the object hierarchy.	Object	object	Object*	Object
	String	An immutable, fixed-length string of Unicode characters.	String	string	String*	String

Source: http://msdn.microsoft.com/en-us/library/aa720713(VS.71).aspx