Example of an Import Task Set Virtual

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A sales representative has been entering details about new clients from Sydney and some reservations they have booked. These new data must now be transferred from a laptop to the application (imported into the application).

Suppose the person data is in one external file; persons.TXT, and the corresponding reservations data in another file; reservations.TXT. These two external files must be merged before they are written to the PERSON and RESERVATION tables. The structure of these files is the same as the structure of the PERSON and RESERVATION tables.

The files contain primary key values for each person and each reservation. These primary key IDs have been generated on an external system. They must not be imported. Instead, your application must be allowed to generate suitable primary key IDs for these new data.

The reservation data includes a foreign key referring to the person primary key in the other file. This foreign key will allow you to join the reservation data with the right person data.

Performance can be gained by retrieving the primary key value once for the entire set of children. This value will be stored in a virtual column of the parent external set.



collapseDefining external sets
collapseDefining the import task
collapseStoring the value if a virtual column of the parent external set



See also

Import Task Set Virtuals

External Sets for Import Tasks