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| '''Fast/Unload''' is a utility whose primary function is to quickly unload data from a
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| Model 204 data file to one or more sequential data sets.
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| The Fast/Unload utility consists of several functional units. One unit is a data extraction facility which reads data from a ''Model 204'' data file. Another unit is a compiler which converts a special data language describing the output format to machine language. The generated machine language
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| actually performs the output function. A third unit is a reporting facility which provides a
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| job log and reports any special conditions or errors that might have occurred during a
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| run.
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| ''Fast/Unload'' can either be invoked directly as a standalone load module or from a User
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| Language program. When invoked as a standalone load module, ''Fast/Unload''
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| enqueues the data file in share mode unless explicitly requested otherwise. If the
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| enqueue fails, ''Fast/Unload'' terminates with an error condition code. It is thus the file
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| manager's job to ensure that when ''Fast/Unload'' is run as a standalone load module,
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| ''Model 204'' does not have the file to be unloaded locked in exclusive mode.
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| The ''Fast/Unload User Language Interface'', purchased as a separate Fast/Unload option,
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| allows one to invoke Fast/Unload using the FastUnload or [[FastUnloadTask method]] of
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| the [[RecordSet class]] or the [[$FunLoad]] function in a User Language program. With this
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| approach, an application builds a set of records to be unloaded, using standard User
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| Language statements; for example, you can reduce unload time by restricting the set of
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| records using indexed Model 204 fields. The Fast/Unload load module runs in a subtask
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| (or PST under CMS) of Model 204. The Fast/Unload User Language Interface also
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| provides the ability to unload data from a Model 204 group.
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| With the Fast/Unload User Language Interface, the processing can be performed either
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| synchronously or asynchronously.
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| A system manager can cancel or examine Fast/Unload requests, and each user can
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| perform the same functions on asynchronous requests that he or she initiated.
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| See [[List of Fast/Unload $functions]] or the [[FastUnloadTask class]] for more information.
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