HP 3000 Manuals HP 3000 Manuals
Chapter 1 Introducing the System Dictionary SDMAIN Program
Product Overview
HP System Dictionary SDMAIN is a program that allows you to access the
System Dictionary product. You can:
* Enter and maintain data in HP System Dictionary
* Report on and make queries about the data residing in HP System
Dictionary
This access is achieved by means of a command language. This manual
describes the HP System Dictionary Command Language--both its syntax and
usage. Examples are given showing how the commands are used within
common types of applications.
If you are a new user of HP System Dictionary, you will need an
understanding of what a data dictionary is along with its purpose and
function.
What is a Data Dictionary?
Just as an ordinary dictionary is a collection of definitions of words, a
data dictionary is a collection of definitions and descriptions of data
that resides on a computer system. In a dictionary, the smallest unit of
information is a word, whereas, in a data dictionary, the smallest unit
of information is a data element.
The data dictionary does not contain the data itself, but contains
metadata--data about data. This metadata can be descriptions and
definitions of various kinds. It can describe such things as:
Data: Names and definitions of data elements
Data Relationships: How data is related to other data
Data Responsibility: Who is responsible for what data
Organizational Structure: The information flow, who uses the data
Location Information: Where files, programs, and reports reside
Security Information: Who has access to what data
A typical example of a piece of metadata is a data element called "SSN"
which represents a piece of data--a social security number. The social
security number itself does not reside in the dictionary, but a
description of that piece of data does. For instance, the data
dictionary might tell you the name of the data element, the storage
length, the display or output length, the type of data (numeric or
character), its sign if the element is numeric, what database or program
that data resides in, and possibly what departments in the organization
use and maintain that data.
The data dictionary, therefore, serves many purposes. You can use it as
a quick directory to the information that resides on a computer
system--where to go to get pieces of data. You can also, however, use it
as one of the primary means for ensuring consistency of data definitions
and preventing data redundancy. This means that programmers and
developers may be required to check the data dictionary for data elements
that already exist on their system before they design a new program.
Therefore, if a data element already exists on the system describing a
social security number (for example, "SSN" ), the dictionary reports this
information and does not allow the programmer to add a new element with
the same name. This helps an organization to save time in program
development by using data definitions that already exist. It also saves
data storage space by preventing data redundancy and helps to standardize
data definitions within an organization.
For a more detailed introduction to what data dictionaries are and how an
organization can use a data dictionary, see the HP primer entitled
Managing Your Information Network: A Data Dictionary Primer (5958-8527).
What is System Dictionary?
System Dictionary provides dictionary capabilities to the 900 Series, HP
3000 computer systems. All of the dictionary functions that are
discussed above, plus others that are discussed later in this manual are
provided by System Dictionary.
The main areas of functionality in System Dictionary are:
1. Defining the Dictionary Environment
2. Defining the Dictionary Structure
3. Defining and Maintaining Data
4. Reporting on Dictionary Contents
You can access all of these functions through the HP System Dictionary
Command Language. Chapter 3 provides an overview of each of these
functional areas. Chapter 4 provides details about each command.
In addition to SDMAIN that is described in this document, HP System
Dictionary provides the following utilities:
* Dictionary/V to HP System Dictionary Conversion Utility (SDCONV) -
translates data definitions from a Dictionary/V database to the
System Dictionary database.
* TurboIMAGE/V and IMAGE/V Database Definition Loader (SDDBD ) - loads
information about an IMAGE/V database structure into System
Dictionary from an IMAGE/V root file.
* VPlus/V Forms Definition Loader (SDVPD) - loads information about
VPlus/V forms into System Dictionary from a VPlus/V forms file.
* TurboIMAGE/V and IMAGE/V Database Creation Utility (SDDBC) - creates
IMAGE schemes and root files from definitions in System Dictionary.
* COBOL Definition Extractor Utility (SDCDE) - creates COBOL copylibs
from definitions in System Dictionary.
These utilities are described in the documents entitled HP System
Dictionary/XL Utilities Reference Manual (32256-90003), HP System
Dictionary/XL General Reference Manual, Volume 2 (32256-90005), and HP
System Dictionary/XL COBOL Definition Extractor Reference Manual
(32257-90001).
The basic System Dictionary concepts are described in the manual entitled
HP System Dictionary/XL General Reference Manual, Volume 1 (32256-90004).
What is the SDMAIN Program?
The program that provides the interface to System Dictionary is the
Dictionary Maintenance Program called SDMAIN. You must run the SDMAIN
program to access the Command Language commands that create, maintain,
and report entries in the dictionary. The SDMAIN program provides access
to the dictionary without requiring a program to be written for each
specific task.
How to use this Manual
This manual is designed to progress from a general description of HP
System Dictionary and its various functional areas to the specific
description of the HP System Dictionary Command Language.
* Chapter 2 explains how to execute the SDMAIN program.
* Chapter 3 provides a conceptual overview of the kinds of functions
and tasks that can be performed by the Command Language, with a
listing of the specific commands that belong in each category.
* Chapter 4 presents the syntax and parameter descriptions of the
Command Language, with a short example of each command.
* Appendix A lists all of the SDMAIN error messages.
* Appendix B provides a summary of the abbreviations for the command
words in the system.