select SUM(BRUTTO)
from PROTOKOL
where (D +  T >  '07.10.2014 8:00:00' and D +  T <  '07.10.2014 20:00:00' )
order by PROTOKOL.D + PROTOKOL.T desc;

select SUM(BRUTTO)
from PROTOKOL
where (D +  T >  '07.10.2014 8:00:00' and D +  T <  '07.10.2014 20:00:00' )

   SELECT
            FIRST 1 D + T            
            FROM PROTOKOL
             left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
            where 
             (    D +  T >  
           (
            SELECT
            FIRST 1 D + T  
            FROM PROTOKOL
            left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
            where 
          (D +  T >  '07.10.2014 8:00:00' and D +  T <  '07.10.2014 20:00:00' ) 
           and NAME_CARGO = 'Магнетитовая'
            order by D + T desc
             ) 
            and  D +  T <  '07.10.2014 23:00:00'  )       
            and NAME_CARGO = 'Магнет. порожняк'

  SELECT
            FIRST 1 D + T  
            FROM PROTOKOL
            left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
            where 
          (D +  T >  '07.10.2014 8:00:00' and D +  T <  '07.10.2014 20:00:00' ) 
           and NAME_CARGO = 'Магнетитовая'
            order by D + T desc

CREATE [UNIQUE] [ASC[ENDING] | [DESC[ENDING]] INDEX indexname
   ON tablename
   { (<col> [, <col> ...]) | COMPUTED BY (expression) }

CREATE  INDEX indexname
   ON tablename
    COMPUTED BY (d+t)

 SELECT
            FIRST 1 D + T            
            FROM PROTOKOL
             left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
            where 
             (    D +  T >  
           (
            SELECT
            FIRST 1 D + T  
            FROM PROTOKOL
            left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
            where 
          (D = '07.10.2014' and  T >  '8:00:00' and T <  '20:00:00' ) 
           and NAME_CARGO = 'Магнетитовая'
            order by D + T desc
             ) 
            and  D = '07.10.2014' and  T <  '23:00:00'  )       
            and NAME_CARGO = 'Магнет. порожняк'

select 
(
select SUM (BRUTTO)
from PROTOKOL
left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
left outer join STATION STATION1 on (PROTOKOL.FK_STATION = STATION1.ID_STATION)
where 
      (D = '07.10.2014' and  T >  '8:00:00' and T <  '21:00:00' ) 
 and NAME_CARGO = 'ГБРУ' 
 )
 - 
 (
select SUM (BRUTTO)
from PROTOKOL
left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
left outer join STATION STATION1 on (PROTOKOL.FK_STATION = STATION1.ID_STATION)
where 
      (D = '07.10.2014' and  T >  '8:00:00' and T <  '21:00:00' ) 
 and NAME_CARGO = 'ГБРУ порожняк' 
 ) from PROTOKOL

select first 1
(
select SUM (BRUTTO)
from PROTOKOL
left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
where 
      (D = '07.10.2014' and  T >  '8:00:00' and T <  '21:00:00' ) 
 and NAME_CARGO = 'ГБРУ' 
 )
 - 
   (
select SUM (BRUTTO)
from PROTOKOL
left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
where 
      (D = '07.10.2014' and  T >  '8:00:00' and T <  '21:00:00' ) 
 and NAME_CARGO = 'ГБРУ порожняк' 
 )
  from PROTOKOL

select 
(
select SUM (BRUTTO)
from PROTOKOL p
left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
left outer join OBJECT OBJECT1 on (PROTOKOL.FK_OBJECT = OBJECT1.ID_OBJECT)
where 
      (p.D = '07.10.2014' and p.T > '11:21:12' ) 
 and NAME_CARGO = 'Магнетитовая'
 )
 - 
 (
select SUM (BRUTTO)
from PROTOKOL p
left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
left outer join OBJECT OBJECT2 on (PROTOKOL.FK_OBJECT = OBJECT1.ID_OBJECT)
where 
       (p.D = '07.10.2014' and p.T > '11:21:12' ) 
 and NAME_CARGO = 'Магнет. порожняк'  
 ) from RDB$DATABASE
 where OBJECT1.STATE_NUMBER = OBJECT2.STATE_NUMBER

 select SUM (BRUTTO * case when NAME_CARGO = 'Магнетитовая' then  1 else -1 end)
from PROTOKOL p
left outer join CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
left outer join OBJECT OBJECT1 on (PROTOKOL.FK_OBJECT = OBJECT1.ID_OBJECT)
where 
    --  (D = '07.10.2014' and  T >  '8:00:00' and T <  '21:00:00' ) 
        (p.D = '07.10.2014' and p.T > '11:21:12' ) 
 and NAME_CARGO in ( 'Магнетитовая',  'Магнет. порожняк'  ) 
 and OBJECT1.STATE_NUMBER = '55844823'

 select SUM (BRUTTO * case when CARGO1.NAME_CARGO = 'Магнетитовая' then  1 else -1 end)
from PROTOKOL p
INNER JOIN CARGO CARGO1 on (PROTOKOL.FK_CARGO = CARGO1.ID_CARGO)
INNER JOIN OBJECT OBJECT1 on (PROTOKOL.FK_OBJECT = OBJECT1.ID_OBJECT)
where 
    --  (D = '07.10.2014' and  T >  '8:00:00' and T <  '21:00:00' ) 
        (p.D = '07.10.2014' and p.T > '11:21:12' ) 
 and CARGO1.NAME_CARGO in ( 'Магнетитовая',  'Магнет. порожняк'  ) 
 and OBJECT1.STATE_NUMBER = '55844823'