Introduction to ENFORM

Summary of ENFORM Features
Overview of ENFORM
058051 Tandem Computers Incorporated 1–9
The dictionary and the database files are shared resources: multiple operators can
access them concurrently. Because ENFORM does not require an exclusive database
and dictionary, they can be shared with other application transactions written in
COBOL, FORTRAN, or TAL.
An advantage of using DDL to produce the dictionary is that the database can
generally be extended or modified without forcing any changes to existing ENFORM
specifications; you simply change the dictionary instead.
Database Searching ENFORM has two processes: (1) the compiler/report writer and (2) the query
processor. The compiler/report writer compiles the ENFORM specifications, accesses
the dictionary to determine the structure of the information to be retrieved, and passes
the specifications and data structure information to the query processor (Figure 1-7).
The query processor then: chooses a strategy for accessing the database; accesses the
files specified in the query; processes the data according to the specifications; and
returns the data to the compiler/report writer for report generation.
Figure 1-7. ENFORM Environment
LIST
Dictionary
Query
Processor
Database
Compiler/
Report Writer
Reports
In the environment illustrated in Figure 1-7, you need to specify what information
should be selected, without worrying about how the data is to be accessed or where it
is stored. The query processor automatically selects a search strategy for accessing the
information by using information from the dictionary and the file system, and by
using its own search algorithms to reduce the number of database accesses (separate
disk reads) required to produce your information.