HP 3000 Manuals HP 3000 Manuals
Dictionary Structure Commands
System Dictionary is based on the Entity-Relationship model. (See the HP
System Dictionary/XL General Reference Manual, Volume 1 (32256-90004) for
a complete description.) Its structure consists of entity types,
relationship types, relationship classes, and attributes. System
Dictionary supports a predefined set of entity types, relationship types,
relationship classes, and attributes known as the core set. (See the HP
System Dictionary/XL General Reference Manual, Volume 1 (32256-90004) for
the complete listing of core set structures.)
Subsystem Support
The purpose of the core set is to provide a standard set of entity types,
relationship types, relationship classes, and attributes that are
commonly used. This supports the description of the following:
* MPE files
* KSAM files
* Image
* HP IMAGE
* HP SQL
* Vplus forms
* MPE accounting structure
* Network Spooler devices and device classes
* Rapid/V (with some conversion)
* Network directory
* COBOL data definitions
* Pascal data definitions (subset of Pascal data types)
* RPG programs
Additionally, you may customize your dictionary to describe your
particular subsystems and applications.
Customizing the Dictionary
Once you begin working in the dictionary, you may discover that a certain
entity type needed in your particular installation is not provided in the
core set. You may create this entity type by means of the structure
command CREATE ENTITY-TYPE. For example, if you need to know which
documents are filed in which filing cabinet, you may create the entity
type filing-cabinet and associate it with (relate it to) the entity type
document. In order to do this, a new relationship type called
file-cabinet contains document would also have to be created.
The ability to make such changes to the System Dictionary structure is
provided by the structure commands. To use these commands, the
dictionary must be opened in customization mode and in either the DA
scope or a scope with extend capability.
You cannot modify a compiled dictionary. If you specify any of the
dictionary structure commands with a compiled dictionary, System
Dictionary issues an error message. Table 3-3 lists the structure
commands and their subcommands. The specific syntax for each of these
commands is shown in Chapter 4, "System Dictionary Commands" .
Table 3-3. Dictionary Structure Commands and Subcommands
---------------------------------------------------------------------------------------------
| | |
| COMMAND | SUBCOMMAND * |
| | |
---------------------------------------------------------------------------------------------
| | |
| ADD | ENTITY-TYPE-ATTRIBUTE | RELATIONSHIP-TYPE-ATTRIBUTE |
| | |
---------------------------------------------------------------------------------------------
| | |
| CREATE | ATTRIBUTE | ENTITY-TYPE | RELATIONSHIP-CLASS | |
| | RELATIONSHIP-TYPE |
| | |
---------------------------------------------------------------------------------------------
| | |
| DELETE | ATTRIBUTE | ENTITY-TYPE | RELATIONSHIP-CLASS | |
| | RELATIONSHIP-TYPE |
| | |
---------------------------------------------------------------------------------------------
| | |
| MODIFY | ATTRIBUTE | ENTITY-TYPE | ENTITY-TYPE-ATTRIBUTE | |
| | RELATIONSHIP-CLASS | RELATIONSHIP-TYPE | |
| | RELATIONSHIP-TYPE-ATTRIBUTE |
| | |
---------------------------------------------------------------------------------------------
| | |
| REMOVE | ENTITY-TYPE-ATTRIBUTE | RELATIONSHIP-TYPE-ATTRIBUTE |
| | |
---------------------------------------------------------------------------------------------
| | |
| RENAME | ATTRIBUTE | ENTITY-TYPE | RELATIONSHIP-CLASS |
| | |
---------------------------------------------------------------------------------------------
| | |
| RESTRUCTURE | |
| | |
---------------------------------------------------------------------------------------------
* Where | means OR.
The following is a list of the dictionary structure commands and a
description of each.
ADD Associates attributes to entity types or relationship
types. The attributes and the entity types or
relationship types must already exist in the dictionary.
CREATE Creates new entity types, relationship classes,
relationship types, and attributes.
DELETE Deletes entity types, relationship classes, relationship
types, and attributes.
MODIFY Changes the characteristics of entity types,
relationship classes, relationship types, relationship
type-attribute pairs, entity type-attribute pairs, and
attributes.
REMOVE Disassociates attributes from entity types or
relationship types. The opposite of the ADD command.
RENAME Renames an entity type, a relationship class, or an
attribute.
RESTRUCTURE Restructures a dictionary, incorporating any structure
changes that you have made. Restructuring is done
automatically when the EXIT command is issued, when you
change the open or name mode, or when you open a new
dictionary.
Example
The following example provides an illustration of how to open the
dictionary, create a new attribute and entity-type, and then associate
the new attribute to the new entity-type.
>DEFINE DICTIONARY = sysdic; Opens the dictionary with the
Dictionary Administrator scope and
>>SCOPE = dictionary-administrator; customization open mode.
>>PASSWORD = da;
>>OPEN MODE = customization.
>CREATE ENTITY-TYPE terminal. Creates a new entity-type called
terminal.
>CREATE ATTRIBUTE terminal-type; Creates a new attribute called
terminal-type as a character
>>TYPE=c; string containing 30 bytes.
>>LENGTH=30.
>ADD ENTITY-TYPE-ATTRIBUTE terminal; Associates the attribute
terminal-type to entity-type
>>ATTRIBUTE = terminal-type. terminal.
>EXIT Exits the SDMAIN program,
restructuring the dictionary to
incorporate the added structure.