Comparison of various data types

The type of Parameter is. NET Framework data Provider-specific. If the type is specified, the value is converted to a. NET Framework data provider type before the value of Parameter is passed to the data source. You can also specify the type of Parameter in a general way by setting the DbType property of the Parameter object to a specific DbType.

The. NET Framework Data provider type of the Parameter object is inferred from the. NET Framework type of the Value of the Parameter object, or from the DbType of the Parameter object. The following table shows the Parameter types inferred from an object passed as an Parameter value or a specified DbType.

. NET Framework Types	System.Data.DbType	SqlDbType	OleDbType	OdbcType	OracleType
bool	Boolean	Bit	Boolean	Bit	Byte
Byte	Byte	TinyInt	Unsignedtinyint	TinyInt	Byte
Byte[]	Binary	VarBinary. If the byte array is larger than the maximum size of VarBinary (8000 bytes), this implicit conversion will fail. For byte arrays larger than 8000 bytes, explicitly set SqlDbType.	VarBinary	Binary	Raw
Char		Inferring SqlDbType from Char is not supported.	Char	Char	Byte
Datetime	Datetime	Datetime	Dbtimestamp	Datetime	Datetime
Decimal	Decimal	Decimal	Decimal	Numeric	Number
Double	Double	Float	Double	Double	Double
Float	Single	Real	Single	Real	Float
Guid	Guid	uniqueidentifier	Guid	uniqueidentifier	Raw
Int16	Int16	SmallInt	SmallInt	SmallInt	Int16
Int32	Int32	Int	Int	Int	Int32
Int64	Int64	Bitint	BigInt	BigInt	Number
Object	Object	Variant	Variant	Inference from Object OdbcType is not supported.	Blob
String	String	NVarChar. If the string is greater than the maximum size of NVarChar (4,000 characters), this implicit conversion will fail. For strings greater than 4,000 characters, explicitly set SqlDbType.	Varwchar	NVarChar	NVarChar
TimeSpan	Time	Inferring SqlDbType from a TimeSpan is not supported.	DBTime	Time	Datetime
UInt16	UInt16	Inferring SqlDbType from UInt16 is not supported.	Unsignedsmallint	Int	UInt16
UInt32	UInt32	Inferring SqlDbType from UInt32 is not supported.	Unsignedint	BigInt	UInt32
UInt64	UInt64	Inferring SqlDbType from UInt64 is not supported.	Unsignedbigint	Numeric	Number
	Ansistring	VarChar	VarChar	VarChar	VarChar
	Ansistringfixedlength	Char	Char	Char	Char
	Currency	Money	Currency	Inferring OdbcType from Currency is not supported.	Number
	Date	Inferring SqlType from Date is not supported.	DBDate	Date	Datetime
	SByte	Inferring SqlType from SByte is not supported.	TinyInt	Inferring OdbcType from SByte is not supported.	SByte
	Stringfixedlength	NChar	WChar	NChar	NChar
	Time	Inference from time to SqlType is not supported.	DBTime	Time	Datetime
	varnumeric inferred SqlDbType.	varnumeric inferred OdbcType.	Number

Attention

The. NET Framework data provider that is provided with the. NET Framework version 1.0 does not verify that the precision and scale of the decimal parameter values are valid, which can cause truncated data to be inserted into the data source. If you are using the. NET Framework version 1.0, verify that the precision and scale of the decimal value is valid before setting the parameter value. In the. NET Framework version 1.1 and later, an exception is thrown when the Decimal parameter value is set with an invalid precision. However, the number of decimal digits beyond the decimal parameter scale will still be truncated.

Attention
for the. NET Framework 1.0 and later versions, you can use System.Data.SqlTypes for System.Data.SqlClient. For more information, see using SqlTypes.

Comparison of various data types