IBM ISERIES SC41-5210-04, User Manual

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Chapter 4. Specifying and selecting files for a Query for
iSeries query
This chapter describes how you select and use one or more database files that are to be queried for
information. Specifying file selections (the first option on the Define the Query display) is the first of the 11
steps that you can use to define a query. This step includes specifying (or changing) what files you want to
select for your query, seeing what files are already selected, and specifying the join characteristics when
more than one file is selected. This step also allows you to select, when necessary, file members and
record formats for the files.
Notes:
1. Although this chapter discusses this step primarily for the task of creating a query definition, most of
the information also applies to the tasks of changing or displaying an existing definition.
2. If you are creating a query, a 1 is already supplied by the system for the Specify file selection option
on the Define the Query display, and it cannot be removed. This is the only option in the definition
process that you must select when you are creating a query.
3. If you make changes to any of the file selection values in this step, Query attempts to keep whatever
parts of the definition that are still valid. For example, if a field in a file being removed from the
definition also exists in a file being added (as a replacement), the field’s uses in other parts of the
definition (such as part of the sort definition) are kept. (However, it is your responsibility to determine
whether the field in the replacement file contains the kind of information you want.)
The displays related to the file selection process are:
v
File selection displays (for one or more files):
– Specify File Selections
– Select Library (optional)
– Select File (optional)
– Select Member (optional)
– Select Record Format (optional)
v
File join displays (for multiple files only):
– Specify Type of Join
– Specify How to Join Files
Specifying file selections for a Query for iSeries query
The file selection process includes selecting each file from which your query will get data and also
specifying the library containing the file, the file member, and the record format (or using the values
supplied by Query when the display first appears). If you select multiple files, the process also includes
specifying the file join characteristics.
After you have selected your definition steps on the Define the Query display and you press the Enter key
or F21 (Select all), the first display that you see is the Specify File Selections display.
© Copyright IBM Corp. 2000, 2002
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