System.Data.SqlTypes Namespace

The System.Data.SqlTypes namespace provides classes for native data types in ssNoVersion. 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.

Remarks

Each data type in SqlTypes has its equivalent data type in SQL Server, 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 ssNoVersion data types and to the members of the SqlDbType enumeration.

SqlBinary

binary, image, timestamp, varbinary

Binary, Image, TimeStamp, VarBinary

SqlBoolean

bit

Bit

SqlByte

tinyint

TinyInt

SqlBytes

binary, image, timestamp, varbinary

Binary, Image, TimeStamp, VarBinary

SqlChars

char, nchar, text, ntext, nvarchar, varchar

Char, NChar, Text, Ntext, NVarChar, VarChar

SqlDateTime

datetime, smalldatetime

DateTime, SmallDateTime

SqlDecimal

numeric, decimal

Decimal

SqlDouble

float

Float

SqlFileStream

varbinary

VarBinary

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

Classes

TypeReason
INullable

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

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.

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.

SqlBytes

Represents a mutable reference type that wraps either a SqlBytes.Buffer or a SqlBytes.Stream.

SqlChars

SqlChars is a mutable reference type that wraps a Char array or a SqlString instance.

SqlCompareOptions

Specifies the compare option values for a SqlString structure.

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 (or -922,337,203,685,477.5808) to 2 -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.

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.

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.

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.

SqlXml

Represents XML data stored in or retrieved from a server.

StorageState

The StorageState enumeration is not intended for use as a stand-alone component, but as an enumeration from which other classes derive standard functionality.