ENFORM User's Guide

Why Use ENFORM Servers
ENFORM Servers
7–2 058058 Tandem Computers Incorporated
Why Use ENFORM
Servers
The following is a list of the types of data that create problems in query processing and
the solution to the problems using ENFORM servers:
Non-Relational Data
Non-relational data refers to files containing data that is not normalized and,
therefore, cannot be processed by ENFORM. An example of unnormalized data is
an employee record containing a field representing an employee’s dependents
where the field occurs a variable number of times depending on another field in
the record. For ENFORM to process the employee record, the dependents should
be separated from the employee record and placed in a dependents file with either
the employee’s number or name specified as a key to identify the dependents.
An ENFORM server can act as the dependents file by reading the records from a
disc file, stripping the variable number of dependent records from each employee
record, and then sending each dependent record to the query processor. This
process can be repeated for each employee record until no more data is needed.
Dirty Data
Dirty data refers to data entered directly from a terminal. The data can contain
blanks, control, and other characters that prevent ENFORM from making proper
comparisons for data selection. An ENFORM server can act as a filter for a
corresponding disc file by taking out the unacceptable characters and presenting
clean records to the query processor.
Concatenated Files
For the purpose of reporting, you may want individual files with the same logical
structure, which reside on one or more systems, to appear as one file to ENFORM.
An ENFORM server can be written to access multiple files and return one record
at a time to the Query Processor. The data supplied by the ENFORM server
appears (to the query processor) to be coming from one file.
Data Encryption
An ENFORM server can be written to read a file containing encrypted data and to
supply the data, in a decoded form, to the Query Processor.
Data Compression
An ENFORM server can be written to supply decompressed data from a
compressed file and send the data to the query processor.