Executes the query, and returns the first column of the first row in the result set returned by the query. Extra columns or rows are ignored.

[Visual Basic]
Shared  OverloadsPublic Function ExecuteScalar( _ 
   ByVal connection As SqlConnection, _ 
   ByVal database As String, _ 
   ByVal commandText As String, _ 
   ByVal commandType As CommandType _ 
) As Object
[C#]
public static object ExecuteScalar(
   SqlConnection connection,
   string database,
   string commandText,
   CommandType commandType
);
[C++]
public: static Object* ExecuteScalar(
   SqlConnection* connection,
   String* database,
   String* commandText,
   CommandType commandType
);
[JScript]
public static function ExecuteScalar(
   SqlConnection connection,
   String database,
   String commandText,
   CommandType commandType
): Object;

Parameters

connection

Represents an open connection to a SQL Server database.

database

Changes the current database for an open System.Data.SqlClient.SqlConnection.

commandText

The text of the query.

commandType

Specifies how a command string is interpreted.

Return Value

The first column of the first row in the result set, or a null reference if the result set is empty.

Remarks

Use the ExecuteScalar method to retrieve a single value (for example, an aggregate value) from a database. This requires less code than using the ExecuteReader method, and then performing the operations necessary to generate the single value using the data returned by a SqlDataReader.

Example

[C#, Visual Basic] The following example creates a SqlCommand and then executes it using ExecuteScalar. The example is passed a string that is a Transact-SQL statement that returns an aggregate result.

[C#]
SqlConnection connection = new SqlConnection("Server=127.0.0.1;Database=Northwind;Uid=sa;Pwd=;");

string customerName = DatabaseUtility.ExecuteScalar(connection, "Northwind", "SELECT CustomerName FROM Customers WHERE CustomerID = 'ALFKI'", CommandType.Text);
[Visual Basic]
Dim connection As New SqlConnection("Server=127.0.0.1;Database=Northwind;Uid=sa;Pwd=;")

Dim customerName As String = DatabaseUtility.ExecuteScalar(connection, "Northwind", "SELECT CustomerName FROM Customers WHERE CustomerID = 'ALFKI'", CommandType.Text)

            

See Also

DatabaseUtility Class | Joel.Net Namespace | DatabaseUtility.ExecuteScalar Overload List