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OracleCommand.ExecuteScalar Method

Executes the query, and returns the first column of the first row in the result set returned by the query as a .NET Framework data type. Extra columns or rows are ignored.

Namespace:  System.Data.OracleClient
Assembly:  System.Data.OracleClient (in System.Data.OracleClient.dll)

'Declaration
Public Overrides Function ExecuteScalar As Object

Return Value

Type: System.Object
The first column of the first row in the result set as a .NET Framework data type, or a null reference if the result set is empty or the result is a REF CURSOR.

Implements

IDbCommand.ExecuteScalar

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 from the data returned by an OracleDataReader.

A typical ExecuteScalar query can be formatted as in the following C# example:

CommandText = "SELECT COUNT(*) FROM Region";
Int32 count = (int32) ExecuteScalar();

The following example creates an OracleCommand and then executes it using ExecuteScalar. The example is passed a string that is an SQL statement that returns an aggregate result, and a string to use to connect to the database.

Public Sub CreateOracleCommand(myScalarQuery As String, connection As OracleConnection)
    Dim command As New OracleCommand(myScalarQuery, connection)
    command.Connection.Open()
    command.ExecuteScalar()
    connection.Close()
End Sub 'CreateOracleCommand

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1
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