Handle data-related errors

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Last Updated: October 29, 2020
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You may want to detect data-related errors in your server-side application code before an attempt is made to update the database. For example, if a field was changed in the client to a value that is outside the acceptable range of values, you can add code in the server-side application to detect the error. In such a case, you set the REJECTED attribute for a row and set the ERROR attribute at the temp-table and dataset levels. When you set the REJECTED attribute in the server for a row, you always set it for the before-table buffer.

Note: You can use either the ERROR or REJECTED attribute for a row when a data related error is detected. Using REJECTED makes it easier for the client part of the application to differentiate between a system-generated error and a data-related error.

Similar to how MERGE-CHANGES handles rows with the ERROR attribute set, MERGE-CHANGES does not merge rows with the REJECTED attribute set.

Set REJECTED for related records

Depending on your business requirements, when you detect an error in a row you may also want to reject all related child rows and rollback all related changes. For example if an error occurs on a ttOrder row, you would:

In addition, you should set the ERROR attribute for the ttOrderLine and ttOrder temp-tables, and also the dsOrderOrderLine dataset.

The following illustration shows the REJECTED attribute set on child temp-table rows and the ERROR attribute set on the temp-table and dataset.

Set the ERROR and REJECTED attributes in the server

The following is an example in which the application sets the REJECTED attribute to TRUE for the before-table buffer row, if an error occurs when validating the data. The application also sets theERROR attribute to TRUE for the before-table and dataset.

`. . . hQuery:GET-FIRST. DO WHILE hBeforeBuffer:AVAILABLE: /* procedure to validate the data */ RUN ValidateData(hBuffer, OUTPUT lValid). IF lValid THEN hBeforeBuffer:SAVE-ROW-CHANGES() NO-ERROR. ELSE ASSIGN hBeforeBuffer:REJECTED = TRUE hBeforeTable:ERROR = TRUE hChangeDataset:ERROR = TRUE. hQuery:GET-NEXT. END. . . .`

. . .
hQuery:GET-FIRST.
DO WHILE hBeforeBuffer:AVAILABLE:
  /* procedure to validate the data */
  RUN ValidateData(hBuffer, OUTPUT lValid).
  IF lValid
  THEN
    hBeforeBuffer:SAVE-ROW-CHANGES() NO-ERROR.
  ELSE
    ASSIGN
      hBeforeBuffer:REJECTED = TRUE
      hBeforeTable:ERROR = TRUE
      hChangeDataset:ERROR = TRUE.

  hQuery:GET-NEXT.
END.
. . .

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Handle data-related errors

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Handle data-related errors