C# Equivalent of SQL Server Datatypes

SQL Server data type	CLR data type (SQL Server)	CLR data type (.NET Framework)
varbinary	SqlBytes, SqlBinary	Byte[]
binary	SqlBytes, SqlBinary	Byte[]
varbinary(1), binary(1)	SqlBytes, SqlBinary	byte, Byte[]
image	None	None
varchar	None	None
char	None	None
nvarchar(1), nchar(1)	SqlChars, SqlString	Char, String, Char[]
nvarchar	SqlChars, SqlString	String, Char[]
nchar	SqlChars, SqlString	String, Char[]
text	None	None
ntext	None	None
uniqueidentifier	SqlGuid	Guid
rowversion	None	Byte[]
bit	SqlBoolean	Boolean
tinyint	SqlByte	Byte
smallint	SqlInt16	Int16
int	SqlInt32	Int32
bigint	SqlInt64	Int64
smallmoney	SqlMoney	Decimal
money	SqlMoney	Decimal
numeric	SqlDecimal	Decimal
decimal	SqlDecimal	Decimal
real	SqlSingle	Single
float	SqlDouble	Double
smalldatetime	SqlDateTime	DateTime
datetime	SqlDateTime	DateTime
sql_variant	None	Object
User-defined type(UDT)	None	user-defined type
table	None	None
cursor	None	None
timestamp	None	None
xml	SqlXml	None

What is the equivalent SQL Server type for the C# long type?

The mapping table is clear - BIGINT is the equivalent of Int64 (which is long in C#).

What are equivalent C# data types for SQL Server's date, time and datetimeoffset?

Here are the equivalent CLR data types for date, time and datetimeoffset SQL Server data types:

date - DateTime, Nullable<DateTime>

time - TimeSpan, Nullable<TimeSpan>

datetimeoffset - DateTimeOffset, Nullable<DateTimeOffset>

Note that you can find a listing of all SQL Server data types and their CLR equivalents here, Mapping CLR Parameter Data

What is the equivalent of SQL Server 2005 IMAGE Datatype in C#

it won't be supported in future

No, not in future. It is not supported now. Extended support for SQL Server 2005 ended 3 years ago!

You can see SQL Server data type mappings in the official documentation. For image you should use DbType.Binary.

SQL XML datatype equivalent in C# .net

I would avoid using a string directly - and especially in you case where you just need to store the data. Either go with SqlXml or something else that gives a reader. For example like this:

var param = cmd.Parameters.Add("@xml", SqlDbType.Xml);
var doc = XDocument.Load(xmlFilePath);
param.Value = doc.CreateReader();
cmd.ExecuteNonQuery();

(Connection and Command object left out).

The important advice here is just not to use a string object yourself, but as you have discovered already ymmv...

What is the equivalent datatype of SQL Server's Numeric in C#

There isn't a direct equivalent, in that there are no built-in .NET types which allow you to specify the precision/scale explicitly as far as I'm aware. There's no fixed-point type like NUMERIC.

decimal and double are the common floating point types in .NET, with decimal implementing decimal floating point (like NUMERIC in T-SQL) and double implementing binary floating point behaviour (like FLOAT and REAL in T-SQL). (There's float as well, which is a smaller binary floating point type.)

You should choose between decimal and double based on what values you're going to represent - I typically think of "man-made", artificial values (particularly money) as being appropriate for decimal, and continuous, natural values (such as physical dimensions) as being appropriate for double.

---

Related Topics