c-sharp-to-sql-data-types.md

title	titleSuffix	description	author	ms.author	ms.date	ms.service	ms.subservice	ms.topic	monikerRange
C# data types	SQL Server Language Extensions	Map data types from C# .NET to SQL Server for input and output data structures, and for input parameters on the sp_execute_external_script.	rwestMSFT	randolphwest	04/29/2024	sql	language-extensions	conceptual	>=sql-server-ver15 || >=sql-server-linux-ver15

C# .NET and SQL Server supported data types

[!INCLUDE sqlserver2019-and-later]

This article maps SQL Server data types to .NET data types (used by C#) for data structures and parameters on sp_execute_external_script.

The following SQL and .NET data types are currently supported for input/output data sets and input/output parameters.

SQL Server data type	.NET data type	Comment
bit	bool
tinyint	byte
smallint	short
int	int
real	float
bigint	long
float	double
nchar(n)	string
nvarchar(n)	string
binary(n)	byte[]
varbinary(n)	byte[]
nvarchar(max)	string
varbinary(max)	byte[]
uniqueidentifier	Guid
char(n)	string
varchar(n)	string
varchar(max)	string
date	DateOnly	.NET 6 and later versions
time	TimeOnly	.NET 6 and later versions
numeric	decimal
decimal	decimal
money	decimal
smallmoney	decimal
smalldatetime	DateTime
datetime	DateTime
datetime2	DateTime

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