IBM Support

IT20692: POOR PERFORMANCE WHEN OJ AND JOIN ON IT HAS SAME TABLE

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APAR status

  • Closed as program error.

Error description

  • Description: DB2 query may show poor performance when the
following conditions are met:
1. The query has one or more Outer Joins
2. There is join on top of Outer Join(s)
2. Row Preserving side of an Outer Join has a table, also used
in the join on top of this OuterJoin.

Local fix

  • 



Problem summary


    

  • ****************************************************************
* USERS AFFECTED:                                              *
* ALL                                                          *
****************************************************************
* PROBLEM DESCRIPTION:                                         *
* See Error Description                                        *
****************************************************************
* RECOMMENDATION:                                              *
* Upgrade to Db2 11.1 Mod 4 Fixpack 4 or higher                *
****************************************************************

    



Problem conclusion


    

  • First fixed in Db2 11.1 Mod 4 Fixpack 4

    



Temporary fix


    

  • 



Comments


    

  • 



APAR Information




    

  • APAR number
    IT20692
    • 

  • Reported component name
    DB2 FOR LUW
    • 

  • Reported component ID
    DB2FORLUW
    • 

  • Reported release
    B10
    • 

  • Status
    CLOSED  PER
    • 

  • PE
    NoPE
    • 

  • HIPER
    NoHIPER
    • 

  • Special Attention
    NoSpecatt / Xsystem
    • 

  • Submitted date
    2017-05-20
    • 

  • Closed date
    2020-01-28
    • 

  • Last modified date
    2020-01-28
    • 





    

  • APAR is sysrouted FROM one or more of the following:
    

    
IT20642
    

    • 

  • APAR is sysrouted TO one or more of the following:
    

    • 



Fix information


    

  • Fixed component name
    DB2 FOR LUW
    • 

  • Fixed component ID
    DB2FORLUW
    • 



Applicable component levels


    








      
          
                    

          

          [{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSEPGG","label":"Db2 for Linux, UNIX and Windows"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.1","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}}]
          

                    

        
        

        

      


      


        

            

            
Document Information


            

            


                        

            Modified date:
            

            28 January 2020
            

            
            
          

        


        

        


      


    


  





    

  



  
    
      

      
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