Pathmaker Programming Guide

Creating DB Requesters
Creating Requesters
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Creating DB
Requesters
DB requester applications provide a quick way of producing a simple application
without writing any service or server code. You create a DB requester application by
creating one or more DB requesters and designating which of the standard services are
accessible from the requester. You can also create one or more MENU requesters for a
DB requester application.
“Creating a DB Requester Application” in Section 3 provides basic information about
DB requester applications and how they are used, and introduces the basic steps for
creating a DB requester application. You should be familiar with this information
before creating a DB requester.
Use Table 5-3, the “DB Requester Application Check List” found at the beginning of
this section, to guide you through the Pathmaker screens and associated tasks
required to create a DB requester application.
Appendix B “How to Operate a DB Requester Application” contains detailed
instructions for an end user operating a Pathmaker DB requester application.
DB Requester Guidelines Remember these important guidelines as you create a DB requester:
You can create a DB requester for the following file types:
Entry-sequenced
Key-sequenced
Relative
If you want to access entry-sequenced or relative files using a DB requester, an
alternate key must exist for the file. The Pathmaker product does not support
courtesy keys.
You cannot create a DB requester that accesses unstructured files.
For a DB requester, you can use the same DDL source code that you would use
with any Pathmaker requester with the following restrictions:
If you identify the entire record as a key field, the Pathmaker application will
use the first group or elementary item in the record as the key.
If you use an OCCURS DEPENDING ON clause, the Pathmaker application
will use the maximum number of occurs items.
Pathmaker DB requesters can handle the maximum Enscribe record length of 4000
bytes.
Record Instance Detail
Screen
One of the Pathmaker screens listed on the “DB Requester Application Check List”
(Table 5-3) is the Record Instance Detail screen. This screen is used only for DB
requesters. The Record Instance Detail screen is where you specify additional
information about one file (DDL record or SQL table object) accessed by a DB
requester.
On this screen, you can specify additional screen formatting information and designate
which of the standard services are available for the file.