Executes the query and returns the first column of the first row in the result set returned by the query. All other columns and rows are ignored.
public abstract object ExecuteScalar ();
The first column of the first row in the result set.
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