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    Oracle error: io_z111_write / unique constraint (xxx50.Z111_ID) violated

    • Article Type: General
    • Product: Aleph
    • Product Version: 19.01

    Problem Symptoms:
    This error repeatedly shows in the pc_server log:

    Oracle error: io_z111_write
    ORA-00001: unique constraint (xxx50.Z111_ID) violated

    Will we have to re-index anything as a result of these errors?

    This error can occur when many updates are occurring at the same time

    The z111 is the Oracle table which contains ADM keywords (patron name, patron address, budget name, etc.).
    This message indicates that the system tried to write a z111 record with the same z111_rec_key value as an existing z111.

    The z111_rec_key is assigned by the io_z111_get_last_sequence routine which reads the existing z111 to see what the highest existing number is in deciding what number to use.

    This error can occur when many updates are occurring at the same time. When the routine gets this error, it will try again (up to ten times) to do the write. If it does try 10 times and still fails, then you will see a different message:

    WARNING: Cannot write Z111 for xxx50

    If you get the unique constraint z111_id message only, there is no need to re-index or to take further action.

    The "Cannot write Z111", in contrast, indicates an *actual* problem and its exact reason must be checked on site.

    Category: Circulation (500)

    • Article last edited: 10/8/2013