SELECT "DateTime"::DATE +
      FLOOR ( EXTRACT ( epoch
      FROM ( "DateTime"::TIMESTAMP - "DateTime"::DATE ) / ( 15 * 60 ) ) ) * 15 * 60 * INTERVAL '1 second' "Время"
                   , round ( SUM ( EXTRACT ( epoch
      FROM "Length" ) * "Count" ) / SUM ( EXTRACT ( epoch
      FROM "Length" ) ) ) "Среднее"
                   , MAX ( "Count" ) "Максимальное"
                   , NULL AS "ОграничениеАТС"
                   , 54 AS "КоличествоАгентов"
      FROM
         (
            SELECT "DateTime"
                               , SUM ( "Delta" ) OVER (
               ORDER BY "DateTime" ) "Count"
                                       , lead ( "DateTime" , 1 , "DateTime" + '5 minute' ) OVER (
               ORDER BY "DateTime" ) - "DateTime" "Length"
               FROM
                  (
                     SELECT "DateTime"
                                                  , "Delta"
                        FROM "CallCenterLineLoad2"
                        WHERE "DateTime" BETWEEN 2016-11-29::DATE
                           AND 2016-11-29::DATE + INTERVAL '23:59:59'
                           AND NOT "Internal"
                           AND "Агент" = any ( '{7296,5891}' ::INT[] )
                     UNION ALL
                     SELECT dt::TIMESTAMP
                     WITH TIME
                        zone AS "Время"
                                                       , 0 AS "Дельта"
                        FROM generate_series ( 2016-11-29::DATE , 2016-11-29::DATE + INTERVAL '23:59:59' , '15 minute' ) AS dt
                  )
                   TT
               ORDER BY 1
         )
          T
      GROUP BY 1
      ORDER BY 1