/// <summary>
/// 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.
/// </summary>
/// <returns></returns>
public object ExecuteScalar()
{
// There must be a valid and open connection.
if (connection == null || connection.State != ConnectionState.Open)
throw new InvalidOperationException("Connection must be valid and open");
// Data readers have to be closed first
if (connection.Reader != null)
throw new MySqlException("There is already an open DataReader associated with this Connection which must be closed first.");
arraySql = SplitSql( cmdText );
updateCount = -1;
MySqlDataReader reader = new MySqlDataReader(this, 0);
reader.NextResult();
object val = null;
if (reader.Read())
val = reader.GetValue(0);
reader.Close();
return val;
}
/// <summary>
/// Overloaded. Sends the CommandText to the Connection and builds a MySqlDataReader.
/// </summary>
/// <returns></returns>
public MySqlDataReader ExecuteReader(CommandBehavior behavior)
{
// There must be a valid and open connection.
if (connection == null || connection.State != ConnectionState.Open)
throw new InvalidOperationException("Connection must be valid and open");
// make sure all readers on this connection are closed
if (connection.Reader != null)
throw new InvalidOperationException("There is already an open DataReader associated with this Connection which must be closed first.");
string sql = cmdText;
if (0 != (behavior & CommandBehavior.KeyInfo))
{
}
if (0 != (behavior & CommandBehavior.SchemaOnly))
{
}
if (0 != (behavior & CommandBehavior.SequentialAccess))
{
}
if (0 != (behavior & CommandBehavior.SingleResult))
{
}
if (0 != (behavior & CommandBehavior.SingleRow))
{
sql = String.Format("SET SQL_SELECT_LIMIT=1;{0};SET sql_select_limit=-1;", cmdText);
}
arraySql = SplitSql( sql );
updateCount = -1;
MySqlDataReader reader = new MySqlDataReader(this, behavior);
// move to the first resultset
reader.NextResult();
connection.Reader = reader;
return reader;
}
