Data Retrieval on SEQ

When opening sequential files, Uniface attempts to establish both read and write access. If this fails, Uniface opens them with read-only access. Users can read data, but any attempt to update the data causes the appropriate warning or error message to be returned.

Because SEQ is based on system-dependent I/O calls, it is not possible for the connector to distinguish between violation of read-only access and any other I/O error. If users have read-only access and they try to write to a sequential file, inappropriate messages can result, including bad file number, or occurrence no longer exists. Remember that there is no locking available at any time; sequential files should be used by single users only. You should take these limitations into account when using the SEQ connector in a production environment.

The retrieveSequential trigger is not supported.

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