Запрос с несколькими подзапросами слишком медленный

Question

Есть ли способ оптимизировать запрос ниже? Я нахожу, что он отображает результат медленный, почти 15 минут, для получения 3500 записей. Я подозреваю, что это из-за подзапросов.

SELECT          
    MSTUDYPROCESS.I_PROCESS_PL,       
    MPROCESS.N_PROCESS_PL C_PART_CODE,       
    MPROCESS.I_LOAD_TYP,         
    MPROCESS.I_ASME_GRP,         
    (          
    SELECT          
     MASMEGRP.N_ASME_GRP       
    FROM          
     MASMEGRP         
    WHERE          
     MASMEGRP.I_ASME_GRP = MPROCESS.I_ASME_GRP    
    )      N_ASME_GRP,   
    MSTUDYPROCESS.Q_COMMON_PARTS_PER_HIT,      
    MSTUDYPROCESS.I_AUTOM_TYP,       
    MSTUDYPROCESS.I_STMPG_PART_TYP,       
    MSTUDYPROCESS.I_BLNK_TYP,       
    MSTUDYPROCESS.I_ASSY_TYP,       
    MSTUDYPROCESS.Q_PARTS_PER_HIT,       
    MSTUDYPROCESS.Q_NMBR_OF_DIES,       
    MSTUDYPROCESS.Q_STN_REQD,       
    MSTUDYPROCESS.L_TOGGLE,        
    MSTUDYPROCESS.Q_SHUT_HGT,       
    MSTUDYPROCESS.X_COMNT,        
    MSTUDYPROCESS.N_PART_PL,        
    MSTUDYPROCESS.N_PART_PL_ADDNL,       
    CASE           
    (          
    SELECT          
     COUNT(*)         
    FROM          
     MPROCESSDEPEND        
    WHERE          
     MPROCESSDEPEND.I_PROCESS_PL = MSTUDYPROCESS.I_PROCESS_PL   
    ) WHEN 0 THEN 0 ELSE 1 END     IS_MASSYDETAIL, 
    CASE           
    (          
    SELECT          
     COUNT(*)         
    FROM          
     MOFFLOAD         
    WHERE          
     MOFFLOAD.I_STDY  = MSTUDYPROCESS.I_STDY    
     AND MOFFLOAD.N_PROCESS_PL = MPROCESS.N_PROCESS_PL    
    ) WHEN 0 THEN 0 ELSE 1 END     IS_MOFFLOAD,  
    (          
    SELECT          
     COUNT(DISTINCT I_MODEL_YR)      
    FROM          
     MLOADFORECAST        
    WHERE          
     MLOADFORECAST.I_STDY  = MSTUDYPROCESS.I_STDY   
     AND MLOADFORECAST.I_PROCESS_PL = MSTUDYPROCESS.I_PROCESS_PL   
    )        NUM_YEARS, 
    EPL.Get_Line_BX(MSTUDYPROCESS.I_STDY, MSTUDYPROCESS.I_PROCESS_PL) BLANK_LINE, 
    MSTUDYPROCESS.I_UPD_TID,        
    MSTUDYPROCESS.D_UPD_LAST        
    FROM           
    MSTUDYPROCESS,         
    MPROCESS          
    WHERE           
    MSTUDYPROCESS.I_STDY = IN_I_STDY      
    AND MPROCESS.I_PROCESS_PL = MSTUDYPROCESS.I_PROCESS_PL     
    ORDER BY          
    MPROCESS.N_PROCESS_PL; 

Answer 1

Try без хранимой процедуры, как этот

SELECT          
MSTUDYPROCESS.I_PROCESS_PL,       
Process_1.N_PROCESS_PL C_PART_CODE,       
Process_1.I_LOAD_TYP,         
Process_1.I_ASME_GRP,         
grp.N_ASME_GRP,   
MSTUDYPROCESS.Q_COMMON_PARTS_PER_HIT,      
MSTUDYPROCESS.I_AUTOM_TYP,       
MSTUDYPROCESS.I_STMPG_PART_TYP,       
MSTUDYPROCESS.I_BLNK_TYP,       
MSTUDYPROCESS.I_ASSY_TYP,       
MSTUDYPROCESS.Q_PARTS_PER_HIT,       
MSTUDYPROCESS.Q_NMBR_OF_DIES,       
MSTUDYPROCESS.Q_STN_REQD,       
MSTUDYPROCESS.L_TOGGLE,        
MSTUDYPROCESS.Q_SHUT_HGT,       
MSTUDYPROCESS.X_COMNT,        
MSTUDYPROCESS.N_PART_PL,        
MSTUDYPROCESS.N_PART_PL_ADDNL,       
CASE DEPEND.NBDEPEND WHEN 0 THEN 0 ELSE 1 END IS_MASSYDETAIL, 
CASE OFFLOAD.NBMOFFLOAD WHEN 0 THEN 0 ELSE 1 END IS_MOFFLOAD,  
LOADFORECAST.NBMLOADFORECAST NUM_YEARS, 
Proc2.I_PRES_LINE BLANK_LINE, 
MSTUDYPROCESS.I_UPD_TID,        
MSTUDYPROCESS.D_UPD_LAST        
    FROM           
    MSTUDYPROCESS inner join MPROCESS Process_1 on Process_1.I_PROCESS_PL  =  MSTUDYPROCESS.I_PROCESS_PL 

    left outer join lateral 
    (
    SELECT MASMEGRP.N_ASME_GRP FROM MASMEGRP         
    WHERE MASMEGRP.I_ASME_GRP = Process_1.I_ASME_GRP 
    fetch first rows only 
    ) grp on 1=1 

    inner join lateral 
    (
    SELECT COUNT(*) NBDEPEND FROM MPROCESSDEPEND        
    WHERE MPROCESSDEPEND.I_PROCESS_PL = MSTUDYPROCESS.I_PROCESS_PL 
    ) DEPEND on 1=1 

    inner join lateral 
    (
    SELECT COUNT(*) NBMOFFLOAD FROM MOFFLOAD         
    WHERE MOFFLOAD.I_STDY  = MSTUDYPROCESS.I_STDY    
    AND MOFFLOAD.N_PROCESS_PL = Process_1.N_PROCESS_PL 
    ) OFFLOAD on 1=1 

    inner join lateral 
    (
    SELECT COUNT(DISTINCT I_MODEL_YR) NBMLOADFORECAST FROM MLOADFORECAST        
    WHERE MLOADFORECAST.I_STDY  = MSTUDYPROCESS.I_STDY   
    AND MLOADFORECAST.I_PROCESS_PL = MSTUDYPROCESS.I_PROCESS_PL  
    ) LOADFORECAST on 1=1 

    left outer join lateral 
    (
    SELECT MLOADFORECAST.I_PRES_LINE 
    FROM MPROCESS Process_2 inner join MLOADFORECAST on  MLOADFORECAST.I_PROCESS_PL= Process_2.I_PROCESS_PL 
    WHERE Process_2.N_PROCESS_PL= Process_1.N_PROCESS_PL 
    and Process_2.I_LOAD_TYP = CASE Process_1.I_LOAD_TYP WHEN 'B' THEN 'X'  WHEN 'X' THEN 'B' END 
    AND MLOADFORECAST.I_STDY= MSTUDYPROCESS.I_STDY 
    ORDER BY MLOADFORECAST.I_MODEL_YR, MLOADFORECAST.I_PRES_LINE 
    FETCH FIRST ROW ONLY 
    ) Proc2 on 1=1 

    WHERE MSTUDYPROCESS.I_STDY = IN_I_STDY      
    ORDER BY Process_1.N_PROCESS_PL;