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| <var class="product">Fast/Unload</var> 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 <var class="product">Fast/Unload</var> utility consists of several functional units. One unit is a data extraction facility which reads data from a <var class="product">Model 204</var> 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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| <var class="product">Fast/Unload</var> 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, <var class="product">Fast/Unload</var>
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| enqueues the data file in share mode unless explicitly requested otherwise. If the
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| enqueue fails, <var class="product">Fast/Unload</var> terminates with an error condition code. It is thus the file
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| manager's job to ensure that when <var class="product">Fast/Unload</var> is run as a standalone load module,
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| <var class="product">Model 204</var> does not have the file to be unloaded locked in exclusive mode.
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| The <var class="product">Fast/Unload User Language Interface</var>, purchased as a separate <var class="product">Fast/Unload</var> option,
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| allows one to invoke <var class="product">Fast/Unload</var> from User Language,
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| using the <var>[[FastUnload (Recordset function)|FastUnload]]</var> or <var>[[FastUnloadTask (Recordset function)|FastUnloadTask]]</var> functions of
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| the <var>[[Recordset class|Recordset]]</var> class or the [[$FunLoad]] function .
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| With this 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 <var class="product">Model 204</var> fields. The <var class="product">Fast/Unload</var> load module runs in a subtask
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| (or PST under CMS) of <var class="product">Model 204</var>.
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| With the <var class="product">Fast/Unload User Language Interface</var>, the processing can be performed either
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| synchronously or asynchronously.
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| A system manager can cancel or examine <var class="product">Fast/Unload</var> 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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| To explore the details, see "[[:Category:Fast/Unload User Language Interface|Components]] of the <var class="product">Fast/Unload User Language Interface</var>".
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| The <var class="product">Fast/Unload User Language Interface</var> also
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| provides the ability to unload data from a Model 204 group.
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| The standalone <var class="product">Fast/Unload</var> load module
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| can also unload a group of files, although without access to group definitions in <var class="product">Model 204</var>.
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