Do not conduct signal operations in an import information editing UOC routine's functions.

• Do not issue alarm() or pause() system calls.
• If you generate a subprocess by fork() or exec(), execute postprocessing on the user side.

Do not use the same shared memory that is used by the target Datareplicator or by any other system.

If hds_uedit() passes COMMIT and its return value is 0 or 4, Datareplicator assumes that one synchronization point was completed. If the import information editing UOC routine's process is aborted due to an error, restart takes place at the synchronization point immediately following the previous synchronization point. You must code the processing in the import information editing UOC routine's functions so that synchronization point processing occurs when COMMIT is passed and so that no duplicate processing occurs when processing is restarted after an abnormal termination.

When you create a UOC routine that accesses a database, use the hds_uend() editing termination function to reference the termination information flag (stopinf) in the interface block (UINTERFACE_BLK). If the termination information indicates forced termination, create the UOC routine so that it executes ROLLBACK on the database system, and then executes DISCONNECT. If the UOC routine executes DISCONNECT without executing ROLLBACK, update processing up to the point of forced termination will be committed by automatic commitment of DISCONNECT. The next time Datareplicator is restarted, there will be an inconsistency in the database and the UOC routine will result in an SQL error.

• discintvl (disconnect issuance interval) is not applicable to an import group using the UOC routine.
• If a trigger is defined for the target table and HiRDB is accessed within the import information editing interface function, the control_trigger parameter in the import environment definition is ignored.

The notes provided here apply to when you create a new import information editing UOC routine.

If you are using an existing import information editing UOC routine, re-link the executable file of the import information editing UOC routine. In this case, verify that the existing import information editing UOC routine does not violate the notes provided here. For details about the linkage procedure, see 8.1 Import information editing UOC routine. If you do not link the programs, an audit trail will be collected.

• When you create an import information editing UOC routine, observe the following rules:
  
  • Execute CONNECT to HiRDB within the hds_ubegin function.
    If this rule is violated, the KFRB03094-W message will be output.
    The subsequent processing depends on the hirdb_audit_trail operand value in the import system definition.
    
  • Do not execute any SQL statement other than CONNECT within the hds_ubegin function.
    If this rule is violated, an audit trail will be collected for any SQL statement specified within the hds_ubegin function, except for CONNECT. If a transaction has not been completed within the hds_ubegin function, an audit trail might be collected for that transaction.
    
  • Execute DISCONNECT to HiRDB within the hds_uend function.
    If this rule is violated, an audit trail will be collected following issuance of DISCONNECT.
    
• If the import information editing UOC routine does not execute any SQL statements, do not specify HiRDB libraries in the link command used to create executable files.
  If this rule is violated, the KFRB03094-W message will be output.
  The subsequent processing depends on the hirdb_audit_trail operand value in the import system definition.
  
• To avoid any unauthorized accesses from the import information editing UOC routine, the Datareplicator administrator must ensure the following:
  
  • The import information editing UOC routine does not allow unauthorized access to the databases.
  • The import information editing UOC routine does not allow tampering by third parties with malicious intent.
  • The owner and access permissions of the import information editing UOC routine are set as shown in the following table.
    

    Table 8-22 Owner and access permissions for an import information editing UOC routine

    Owner and access permission		Information to be specified
    Owner	User ID	HiRDB Datareplicator administrator
    	Group ID	HiRDB administrator's group ID
    Access permission	Owner	r-x (read and execute permissions)
    	Group	--- (Not accessible)
    	Other	--- (Not accessible)

    Because there is no permission to write files, if you re-create the executable files of the import information editing UOC routine, delete the existing executable files, and then create the new executable files.

    
    

A table for which a referential constraint has been defined cannot be specified in an import information editing UOC routine.

If you will be using the extended syslog facility, re-link the UOC routine by using the linkage procedure described in 8.1.2 Creating an import information editing UOC routine (UNIX).

If the UOC routine is not linked as instructed, the extended syslog facility will not be applicable to syslogfile that is output for the import information editing UOC routine.