DB2 V8fp5 SQLSTATE 01517

Problem summary

• USERS AFFECTED:
  All
  
  PROBLEM DESCRIPTION:
  Inserting large amount of multi-byte character data into a
  CLOB column can result in data corruption. The result data in
  the CLOB column in such case would contain characters 0xFC.
  
  
  PROBLEM SUMMARY:
  The problem can occur when working with large lob data (>128kB).
  The lob data is processed in chunks as they are passed by the
  client.  When an internal lob processing buffer containg the
  data chunks is full and there is still data to process, the lob
  data is translated by codepage conversion functions, moved into
  a temporary table and next chunk of data is processed.  In this
  particular defect situation the buffer full condition occurs in
  the middle of the multi-byte character.  The last byte in the
  buffer is not valid multi-byte character so it suppose to be
  remembered and used as the first character of the following
  chunk.  Due to a defect this dangling character is dropped,
  causing all the next multi-byte characters in the following
  chunk to be byte shifted.
  
  Good data:
   006A0061  00760061  002E006C  0061006E    .j.a.v.a...l.a.n
   0067002E  00530074  00720069  006E0067    .g...S.t.r.i.n.g
   0022003E  003C0021  005B0043  00440041    .".>.<.!.[.C.D.A
  
  Bad data (byte shifted):
   74007200  69006E00  67002200  3E003C00    t.r.i.n.g.".>.<.
   21005B00  43004400  41005400  41005B00    !.[.C.D.A.T.A.[.
   63006F00  6D002E00  61007000  74007200    c.o.m...a.p.t.r.
  
  
  Since these byte shifted characters may be invalid (according to
  the used codepage), the the codepage conversion functions can
  throw a warning like this:
  
    SQLSTATE 01517:  A character that could not be converted was
    replaced with a substitute character.
  
  
  A db2 trace of the problem would show errors SQLO_DBCSTRUNC
  followed by SQLO_BUFFSMALL:
  
  | | | sqlnlscpcv data[probe 13]
  | | | | sqlnlsCodePageConvert entry
  | | | | | sqlnlscpcv_noUTF entry
  | | | | | sqlnlscpcv_noUTF data[probe 1]
  | | | | | | sqlnls_valtab entry
  | | | | | | sqlnls_valtab exit
  | | | | | sqlnlscpcv_noUTF exit[rc=0x870F00C0=SQLO_DBCSTRUNC]
  | | | | sqlnlsCodePageConvert data[probe 170]
  | | | | sqlnlsCodePageConvert exit[rc=0x870F00C0=SQLO_DBCSTRUNC]
  | | | sqlnlscpcv exit[rc=0x870F00C0=SQLO_DBCSTRUNC]
  | | sqlnlscpcv exit[rc=0x870F00BC=SQLO_BUFFSMALL]
  | sqlocpcv exit[rc=0x870F00BC=SQLO_BUFFSMALL]
  sqlricpcv exit[rc=0x870F00BC=SQLO_BUFFSMALL]
  sqlri_write_lob_field entry
  

Problem conclusion

• First fixed in DB2 UDB Version 8, FixPak 5 (s040212).
  

Temporary fix

• 
  

Comments

• 
  

APAR Information

• APAR number

  JR25158

• Reported component name

  DB2 UDB WSE WIN

• Reported component ID

  5765F3501

• Reported release

  820

• Status

  CLOSED PER

• PE

  NoPE

• HIPER

  NoHIPER

• Special Attention

  NoSpecatt

• Submitted date

  2006-10-30

• Closed date

  2006-10-30

• Last modified date

  2006-10-30

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

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

Fix information

• Fixed component name

  DB2 UDB WSE WIN

• Fixed component ID

  5765F3501

Applicable component levels

• R810 PSN

  UP

• R820 PSN

  UP

• R910 PSN

  UP