Systems Management: Common Information Model (CIM)
Copyright © 1998 The Open Group

Guidelines for CIM Usage

General

Method descriptions are recommended and must, at a minimum, indicate that method's side-effects (pre- and post-conditions).
Associations must not be declared as subtypes of classes that are not associations.
Although the Override qualifier allows the overridden property, method or reference to be renamed, this is discouraged because it introduces additional names into the schema and makes instances harder to interpret.
As a general rule, it is recommended that class names should not be reused as part of property or method names. Property and method names are already unique within their defining class.
To enable information sharing between different CIM implementations, the MAXLEN qualifier should be used to specify the maximum length of string properties. This qualifier must always be present for string properties used as keys.
A class that has no ABSTRACT qualifier must define, or inherit, key properties.
Leading underscores should not be used in identifiers, and must not be used in the standard schemas.

Mapping of Octet Strings

Most management models, including SNMP and DMI, support octet strings as data types. The octet string data type represents arbitrary numeric or textual data. This data is stored as an indexed byte array of unlimited, but fixed size. Typically, the first N bytes indicate the actual string length. Since some environments only reserve the first byte, they do not support octet strings larger than 255 bytes.

In CIM Version 2.0, CIM does not support octet strings as a separate data type. To map octet strings, it is recommended that the equivalent CIM property be defined as an array of unsigned 8-bit integers (uint8). The first four bytes of the array contain the length of the octet data: byte 0 is the most significant byte of the length; byte 3 is the least significant byte of the length. The octet data starts at byte 4.

SQL Reserved Words

It is recommended that SQL reserved words be avoided in the selection of class and property names. This particularly applies to property names, since class names are prefixed by the schema name, making a clash with a reserved word unlikely.

The current set of SQL reserved words are listed below:

From sql1992.txt:

AFTER ALIAS ASYNC BEFORE
BOOLEAN BREADTH COMPLETION CALL
CYCLE DATA DEPTH DICTIONARY
EACH ELSEIF EQUALS GENERAL
IF IGNORE LEAVE LESS
LIMIT LOOP MODIFY NEW
NONE OBJECT OFF OID
OLD OPERATION OPERATORS OTHERS
PARAMETERS PENDANT PREORDER PRIVATE
PROTECTED RECURSIVE REF REFERENCING
REPLACE RESIGNAL RETURN RETURNS
ROLE ROUTINE ROW SAVEPOINT
SEARCH SENSITIVE SEQUENCE SIGNAL
SIMILAR SQLEXCEPTION SQLWARNING STRUCTURE
TEST THERE TRIGGER TYPE
UNDER VARIABLE VIRTUAL VISIBLE
WAIT WHILE WITHOUT

From sql1992.txt (Annex E):

ABSOLUTE ACTION ADD ALLOCATE
ALTER ARE ASSERTION AT
BETWEEN BIT BIT_LENGTH BOTH
CASCADE CASCADED CASE CAST
CATALOG CHAR_LENGTH CHARACTER_LENGTH COALESCE
COLLATE COLLATION COLUMN CONNECT
CONNECTION CONSTRAINT CONSTRAINTS CONVERT
CORRESPONDING CROSS CURRENT_DATE CURRENT_TIME
CURRENT_TIMESTAMP CURRENT_USER DATE DAY
DEALLOCATE DEFERRABLE DEFERRED DESCRIBE
DESCRIPTOR DIAGNOSTICS DISCONNECT DOMAIN
DROP ELSE END-EXEC EXCEPT
EXCEPTION EXECUTE EXTERNAL EXTRACT
FALSE FIRST FULL GET
GLOBAL HOUR IDENTITY IMMEDIATE
INITIALLY INNER INPUT INSENSITIVE
INTERSECT INTERVAL ISOLATION JOIN
LAST LEADING LEFT LEVEL
LOCAL LOWER MATCH MINUTE
MONTH NAMES NATIONAL NATURAL
NCHAR NEXT NO NULLIF
OCTET_LENGTH ONLY OUTER OUTPUT
OVERLAPS PAD PARTIAL POSITION
PREPARE PRESERVE PRIOR READ
RELATIVE RESTRICT REVOKE RIGHT
ROWS SCROLL SECOND SESSION
SESSION_USER SIZE SPACE SQLSTATE
SUBSTRING SYSTEM_USER TEMPORARY THEN
TIME TIMESTAMP TIMEZONE_HOUR TIMEZONE_MINUTE
TRAILING TRANSACTION TRANSLATE TRANSLATION
TRIM TRUE UNKNOWN UPPER
USAGE USING VALUE VARCHAR
VARYING WHEN WRITE YEAR
ZONE

From sql3part2.txt (Annex E):

ACTION ACTOR AFTER ALIAS
ASYNC ATTRIBUTES BEFORE BOOLEAN
BREADTH COMPLETION CURRENT_PATH CYCLE
DATA DEPTH DESTROY DICTIONARY
EACH ELEMENT ELSEIF EQUALS
FACTOR GENERAL HOLD IGNORE
INSTEAD LESS LIMIT LIST
MODIFY NEW NEW_TABLE NO
NONE OFF OID OLD
OLD_TABLE OPERATION OPERATOR OPERATORS
PARAMETERS PATH PENDANT POSTFIX
PREFIX PREORDER PRIVATE PROTECTED
RECURSIVE REFERENCING REPLACE ROLE
ROUTINE ROW SAVEPOINT SEARCH
SENSITIVE SEQUENCE SESSION SIMILAR
SPACE SQLEXCEPTION SQLWARNING START
STATE STRUCTURE SYMBOL TERM
TEST THERE TRIGGER TYPE
UNDER VARIABLE VIRTUAL VISIBLE
WAIT WITHOUT

From sql3part4.txt (Annex E):

CALL DO ELSEIF EXCEPTION
IF LEAVE LOOP OTHERS
RESIGNAL RETURN RETURNS SIGNAL
TUPLE WHILE

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Index

AFTER	ALIAS	ASYNC	BEFORE
BOOLEAN	BREADTH	COMPLETION	CALL
CYCLE	DATA	DEPTH	DICTIONARY
EACH	ELSEIF	EQUALS	GENERAL
IF	IGNORE	LEAVE	LESS
LIMIT	LOOP	MODIFY	NEW
NONE	OBJECT	OFF	OID
OLD	OPERATION	OPERATORS	OTHERS
PARAMETERS	PENDANT	PREORDER	PRIVATE
PROTECTED	RECURSIVE	REF	REFERENCING
REPLACE	RESIGNAL	RETURN	RETURNS
ROLE	ROUTINE	ROW	SAVEPOINT
SEARCH	SENSITIVE	SEQUENCE	SIGNAL
SIMILAR	SQLEXCEPTION	SQLWARNING	STRUCTURE
TEST	THERE	TRIGGER	TYPE
UNDER	VARIABLE	VIRTUAL	VISIBLE
WAIT	WHILE	WITHOUT

ABSOLUTE	ACTION	ADD	ALLOCATE
ALTER	ARE	ASSERTION	AT
BETWEEN	BIT	BIT_LENGTH	BOTH
CASCADE	CASCADED	CASE	CAST
CATALOG	CHAR_LENGTH	CHARACTER_LENGTH	COALESCE
COLLATE	COLLATION	COLUMN	CONNECT
CONNECTION	CONSTRAINT	CONSTRAINTS	CONVERT
CORRESPONDING	CROSS	CURRENT_DATE	CURRENT_TIME
CURRENT_TIMESTAMP	CURRENT_USER	DATE	DAY
DEALLOCATE	DEFERRABLE	DEFERRED	DESCRIBE
DESCRIPTOR	DIAGNOSTICS	DISCONNECT	DOMAIN
DROP	ELSE	END-EXEC	EXCEPT
EXCEPTION	EXECUTE	EXTERNAL	EXTRACT
FALSE	FIRST	FULL	GET
GLOBAL	HOUR	IDENTITY	IMMEDIATE
INITIALLY	INNER	INPUT	INSENSITIVE
INTERSECT	INTERVAL	ISOLATION	JOIN
LAST	LEADING	LEFT	LEVEL
LOCAL	LOWER	MATCH	MINUTE
MONTH	NAMES	NATIONAL	NATURAL
NCHAR	NEXT	NO	NULLIF
OCTET_LENGTH	ONLY	OUTER	OUTPUT
OVERLAPS	PAD	PARTIAL	POSITION
PREPARE	PRESERVE	PRIOR	READ
RELATIVE	RESTRICT	REVOKE	RIGHT
ROWS	SCROLL	SECOND	SESSION
SESSION_USER	SIZE	SPACE	SQLSTATE
SUBSTRING	SYSTEM_USER	TEMPORARY	THEN
TIME	TIMESTAMP	TIMEZONE_HOUR	TIMEZONE_MINUTE
TRAILING	TRANSACTION	TRANSLATE	TRANSLATION
TRIM	TRUE	UNKNOWN	UPPER
USAGE	USING	VALUE	VARCHAR
VARYING	WHEN	WRITE	YEAR
ZONE

ACTION	ACTOR	AFTER	ALIAS
ASYNC	ATTRIBUTES	BEFORE	BOOLEAN
BREADTH	COMPLETION	CURRENT_PATH	CYCLE
DATA	DEPTH	DESTROY	DICTIONARY
EACH	ELEMENT	ELSEIF	EQUALS
FACTOR	GENERAL	HOLD	IGNORE
INSTEAD	LESS	LIMIT	LIST
MODIFY	NEW	NEW_TABLE	NO
NONE	OFF	OID	OLD
OLD_TABLE	OPERATION	OPERATOR	OPERATORS
PARAMETERS	PATH	PENDANT	POSTFIX
PREFIX	PREORDER	PRIVATE	PROTECTED
RECURSIVE	REFERENCING	REPLACE	ROLE
ROUTINE	ROW	SAVEPOINT	SEARCH
SENSITIVE	SEQUENCE	SESSION	SIMILAR
SPACE	SQLEXCEPTION	SQLWARNING	START
STATE	STRUCTURE	SYMBOL	TERM
TEST	THERE	TRIGGER	TYPE
UNDER	VARIABLE	VIRTUAL	VISIBLE
WAIT	WITHOUT