User guide

Establishing the Query Environment
Developing an ENFORM Query
058058 Tandem Computers Incorporated 3–5
Figure 3-3. The Effect of an ?ASSIGN Command
Query Compiler
Report Writer
RECORD parts.
FILE IS
$mkt.sample.parts
•••
Internal Table
Dictionary
:ENFORM
>?ASSIGN parts TO test
>OPEN parts;
>LIST parts;
Assign:
parts
$mkt.sample.test
Record Description:
parts
$mkt.sample.parts
•••
Report
Query
Processor
$mkt.sample.parts
$mkt.sample.test
Data Base
Using the ?ASSIGN command is useful when you want to test a query that would
normally retrieve a large amount of data. Instead, copy a small portion of the record
occurrences to be retrieved to a new physical file, specify that file name in an ?ASSIGN
command, and then test the query.
Using the ?ASSIGN command also makes maintenance easier. If the ?ASSIGN
command is specified and the data file is moved or renamed, simply change the
?ASSIGN statement instead of recompiling the dictionary.