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DbCommand.ExecuteScalar Method

Definition

Executes the command and returns the first column of the first row in the first returned result set. All other columns, rows and result sets are ignored.

public:
 abstract System::Object ^ ExecuteScalar();
public abstract object ExecuteScalar ();
public abstract object? ExecuteScalar ();
abstract member ExecuteScalar : unit -> obj
Public MustOverride Function ExecuteScalar () As Object

Returns

The first column of the first row in the first result set.

Implements

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 performing the operations necessary to generate the single value using the data returned by a DbDataReader.

If the first column of the first row in the result set is not found, a null reference (Nothing in Visual Basic) is returned. If the value in the database is null, the query returns DBNull.Value.

Applies to

See also