SELECT  
        c1
       ,c2
 FROM
      -- ================================                                    
      (                   
       SELECT 
              c1
            , c2
           -- ---------------------------------------------------------
           , @rownum := @rownum +1 rownum
            -- ---------------------------------------------------------
            , CASE WHEN @cc1 = c1 THEN @rnum := @rnum + 1
                   WHEN (( @cc1 <> '' ) OR ( @cc1 <> c1 ) ) THEN @rnum := 1
              END rogic
            , @rnum RANKKK, @cc1 := c1
            -- ---------------------------------------------------------
         FROM (
                         SELECT 'K' c1, '003' c2
               UNION ALL SELECT 'K' c1, '001' c2
               UNION ALL SELECT 'K' c1, '002' c2
               UNION ALL SELECT 'F' c1, '001' c2
               UNION ALL SELECT 'F' c1, '002' c2
               UNION ALL SELECT 'E' c1, '011' c2
               UNION ALL SELECT 'E' c1, '013' c2
               UNION ALL SELECT 'E' c1, '012' c2
              ) m
             -- ---------------------------------------------------------
             , (SELECT @rownum := 0, @rnum := 0,@cc1 := '' ) D
             -- ---------------------------------------------------------
        -- ---------------------------------------------------------
        ORDER BY c1, c2 ASC
        -- ---------------------------------------------------------                            
      ) mm
WHERE RANKKK = 1