HP DDL D40, Справочное руководство

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Definitions and Records
Data Definition Language (DDL) Reference Manual — 426798-002
5 -2
Exceptions for Specifying Definition Clauses
This form defines a group of fields or groups. A group DEFINITION statement
consists of a name and any of the field definition clauses that are legal for groups,
terminated by a period and followed by one or more field or group descriptions.
The entire group DEFINITION statement is terminated by END.
Reference
This form defines a field or group by referring to a previous definition. A reference
DEFINITION statement copies an existing definition, giving it a new name. The
new definition can be given its own attributes, which can override all the source
definition attributes except for data type and size.
The following syntax summaries show the three forms of the DEFINITION statement,
with brief descriptions of the definition clauses, most of which specify definition
attributes.
Section 6, Definition Attributes , gives complete syntax, descriptions, and
guidelines for these clauses.
Exceptions for Specifying Definition Clauses
You can specify definition clauses in any order for a field or group, with these
exceptions:
•
Any level 88 condition-name clauses and level 89 enumeration clauses must follow
the first period in a field definition or description. A single-field definition that has
one or more of these clauses must also have BEGIN before the first period and
END after the last clause.
•
The level 66 RENAMES clause must immediately precede END in a group
definition.
•
All clauses except level 88, level 89, and level 66 clauses must precede the first
period in a definition or description.
•
END must follow all clauses in a definition. A single-field definition that includes
BEGIN must also include END; other single-field definitions cannot include END.
All group definitions must include END.