SELECT c.Numero_Tarjeta, c.Nombre, c.Apellidos, COUNT(c.Numero_Tarjeta) AS Total_Compras_2018
  FROM CLIENTES_HIPERBER c
  LEFT OUTER JOIN MOVIMIENTOS_CLUB_HIPERBER m
    ON m.Numero_Tarjeta = c.Numero_Tarjeta
 WHERE (m.Fecha_Compra > '2018') AND (m.Fecha_Compra < '2019') AND (c.Empleado = 'S')
 GROUP BY c.Numero_Tarjeta, c.Nombre, c.Apellidos
 ORDER BY Total_Compras_2018 DES