Not all of the reserved keywords are reserved in Firebird and not all are used (yet). However, anything new in Firebird will always use the standard name if it is available. Thus, it is an excellent precaution to avoid defining identifiers that have the potential to become reserved in Firebird's SQL.

The Cost of Blind Ignorance

If you decide to use potentially reserved words as identifiers for database objects, regardless of the consequences, you build a future cost into your databases: if a newer on-disk structure (ODS) version implements that word as a reserved keyword, both your databases and your applications will have to be modified in order to make your databases usable under the new server version. You will have two ways to do this, both pervasive:

• Redefine the identifier by surrounding it with double-quotes. It then becomes case-sensitive. All references everywhere must refer to the identifier using the quoted name OR
• Redefine the identifier by renaming it to a word that has no potential to become reserved (as should have been done originally, anyway!) So — for example — rename STATE to something like STATE0 or CNT_STATE.

Either way, you will have a lot of search-and-replace ahead of you. All dependencies on the object will have to be removed before you can perform either change. Compiled code that depends on this object (stored procedures, triggers, relational and CHECK constraints, etc.) will have to be modified in order to refer to the new object identifier. Likewise, all references to the object in application code will have to be corrected to the new situation.

SQL-92	SQL-99	SQL-2003
ABSOLUTE	ABSOLUTE
ACTION	ACTION
ADD	ADD	ADD
	AFTER
ALL	ALL	ALL
ALLOCATE	ALLOCATE	ALLOCATE
ALTER	ALTER	ALTER
AND	AND	AND
ANY	ANY	ANY
ARE	ARE	ARE
	ARRAY	ARRAY
AS	AS	AS
ASC	ASC
	ASENSITIVE	ASENSITIVE
ASSERTION	ASSERTION
	ASYMMETRIC	ASYMMETRIC
AT	AT	AT
	ATOMIC	ATOMIC
AUTHORIZATION	AUTHORIZATION	AUTHORIZATION
AVG
	BEFORE
BEGIN	BEGIN	BEGIN
BETWEEN	BETWEEN	BETWEEN
		BIGINT
	BINARY	BINARY
BIT	BIT
BIT_LENGTH
	BLOB	BLOB
	BOOLEAN	BOOLEAN
BOTH	BOTH	BOTH
	BREADTH
BY	BY	BY
CALL	CALL	CALL
		CALLED
CASCADE	CASCADE
CASCADED	CASCADED	CASCADED
CASE	CASE	CASE
CAST	CAST	CAST
CATALOG	CATALOG
CHAR	CHAR	CHAR
CHAR_LENGTH
CHARACTER	CHARACTER	CHARACTER
CHARACTER_LENGTH
CHECK	CHECK	CHECK
	CLOB	CLOB
CLOSE	CLOSE	CLOSE
COALESCE
COLLATE	COLLATE	COLLATE
COLLATION	COLLATION
COLUMN	COLUMN	COLUMN
COMMIT	COMMIT	COMMIT
CONDITION	CONDITION	CONDITION
CONNECT	CONNECT	CONNECT
CONNECTION	CONNECTION
CONSTRAINT	CONSTRAINT	CONSTRAINT
CONSTRAINTS	CONSTRAINTS
	CONSTRUCTOR
CONTAINS
CONTINUE	CONTINUE	CONTINUE
CONVERT
CORRESPONDING	CORRESPONDING	CORRESPONDING
COUNT
CREATE	CREATE	CREATE
CROSS	CROSS	CROSS
	CUBE	CUBE
CURRENT	CURRENT	CURRENT
CURRENT_DATE	CURRENT_DATE	CURRENT_DATE
	CURRENT_DEFAULT_TRANSFORM_GROUP	CURRENT_DEFAULT_TRANSFORM_GROUP
CURRENT_PATH	CURRENT_PATH	CURRENT_PATH
	CURRENT_ROLE	CURRENT_ROLE
CURRENT_TIME	CURRENT_TIME	CURRENT_TIME
CURRENT_TIMESTAMP	CURRENT_TIMESTAMP	CURRENT_TIMESTAMP
	CURRENT_TRANSFORM_GROUP_FOR_TYPE	CURRENT_TRANSFORM_GROUP_FOR_TYPE
CURRENT_USER	CURRENT_USER	CURRENT_USER
CURSOR	CURSOR	CURSOR
	CYCLE	CYCLE
	DATA
DATE	DATE	DATE
DAY	DAY	DAY
DEALLOCATE	DEALLOCATE	DEALLOCATE
DEC	DEC	DEC
DECIMAL	DECIMAL	DECIMAL
DECLARE	DECLARE	DECLARE
DEFAULT	DEFAULT	DEFAULT
DEFERRABLE	DEFERRABLE
DEFERRED	DEFERRED
DELETE	DELETE	DELETE
	DEPTH
	DEREF	DEREF
DESC	DESC
DESCRIBE	DESCRIBE	DESCRIBE
DESCRIPTOR	DESCRIPTOR
DETERMINISTIC	DETERMINISTIC	DETERMINISTIC
DIAGNOSTICS	DIAGNOSTICS
DISCONNECT	DISCONNECT	DISCONNECT
DISTINCT	DISTINCT	DISTINCT
DO	DO	DO
DOMAIN	DOMAIN
DOUBLE	DOUBLE	DOUBLE
DROP	DROP	DROP
	DYNAMIC	DYNAMIC
	EACH	EACH
		ELEMENT
ELSE	ELSE	ELSE
ELSEIF	ELSEIF	ELSEIF
END	END	END
	EQUALS
ESCAPE	ESCAPE	ESCAPE
EXCEPT	EXCEPT	EXCEPT
EXCEPTION	EXCEPTION
EXEC	EXEC	EXEC
EXECUTE	EXECUTE	EXECUTE
EXISTS	EXISTS	EXISTS
EXIT	EXIT	EXIT
EXTERNAL	EXTERNAL	EXTERNAL
EXTRACT
FALSE	FALSE	FALSE
FETCH	FETCH	FETCH
	FILTER	FILTER
FIRST	FIRST
FLOAT	FLOAT	FLOAT
FOR	FOR	FOR
FOREIGN	FOREIGN	FOREIGN
FOUND	FOUND
	FREE	FREE
FROM	FROM	FROM
FULL	FULL	FULL
FUNCTION	FUNCTION	FUNCTION
	GENERAL
GET	GET	GET
GLOBAL	GLOBAL	GLOBAL
GO	GO
GOTO	GOTO
GRANT	GRANT	GRANT
GROUP	GROUP	GROUP
	GROUPING	GROUPING
HANDLER	HANDLER	HANDLER
HAVING	HAVING	HAVING
	HOLD	HOLD
HOUR	HOUR	HOUR
IDENTITY	IDENTITY	IDENTITY
IF	IF	IF
IMMEDIATE	IMMEDIATE	IMMEDIATE
IN	IN	IN
INDICATOR	INDICATOR	INDICATOR
INITIALLY	INITIALLY
INNER	INNER	INNER
INOUT	INOUT	INOUT
INPUT	INPUT	INPUT
INSENSITIVE	INSENSITIVE	INSENSITIVE
INSERT	INSERT	INSERT
INT	INT	INT
INTEGER	INTEGER	INTEGER
INTERSECT	INTERSECT	INTERSECT
INTERVAL	INTERVAL	INTERVAL
INTO	INTO	INTO
IS	IS	IS
ISOLATION	ISOLATION
	ITERATE	ITERATE
JOIN	JOIN	JOIN
KEY	KEY
LANGUAGE	LANGUAGE	LANGUAGE
	LARGE	LARGE
LAST	LAST
	LATERAL	LATERAL
LEADING	LEADING	LEADING
LEAVE	LEAVE	LEAVE
LEFT	LEFT	LEFT
LEVEL	LEVEL
LIKE	LIKE	LIKE
LOCAL	LOCAL	LOCAL
	LOCALTIME	LOCALTIME
	LOCALTIMESTAMP	LOCALTIMESTAMP
	LOCATOR
LOOP	LOOP	LOOP
LOWER
	MAP
MATCH	MATCH	MATCH
MAX
		MEMBER
		MERGE
	METHOD	METHOD
MIN
MINUTE	MINUTE	MINUTE
	MODIFIES	MODIFIES
MODULE	MODULE	MODULE
MONTH	MONTH	MONTH
		MULTISET
NAMES	NAMES
NATIONAL	NATIONAL	NATIONAL
NATURAL	NATURAL	NATURAL
NCHAR	NCHAR	NCHAR
	NCLOB	NCLOB
	NEW	NEW
NEXT	NEXT
NO	NO	NO
	NONE	NONE
NOT	NOT	NOT
NULL	NULL	NULL
NULLIF
NUMERIC	NUMERIC	NUMERIC
	OBJECT
OCTET_LENGTH
OF	OF	OF
	OLD	OLD
ON	ON	ON
ONLY	ONLY	ONLY
OPEN	OPEN	OPEN
OPTION	OPTION
OR	OR	OR
ORDER	ORDER	ORDER
	ORDINALITY
OUT	OUT	OUT
OUTER	OUTER	OUTER
OUTPUT	OUTPUT	OUTPUT
	OVER	OVER
OVERLAPS	OVERLAPS	OVERLAPS
PAD	PAD
PARAMETER	PARAMETER	PARAMETER
PARTIAL	PARTIAL
	PARTITION	PARTITION
PATH	PATH
POSITION
PRECISION	PRECISION	PRECISION
PREPARE	PREPARE	PREPARE
PRESERVE	PRESERVE
PRIMARY	PRIMARY
PRIOR	PRIOR
PRIVILEGES	PRIVILEGES
PROCEDURE	PROCEDURE	PROCEDURE
PUBLIC	PUBLIC
	RANGE	RANGE
READ	READ
	READS	READS
REAL	REAL	REAL
	RECURSIVE	RECURSIVE
	REF	REF
REFERENCES	REFERENCES	REFERENCES
	REFERENCING	REFERENCING
RELATIVE	RELATIVE
	RELEASE	RELEASE
REPEAT	REPEAT	REPEAT
RESIGNAL	RESIGNAL	RESIGNAL
RESTRICT	RESTRICT
	RESULT	RESULT
RETURN	RETURN	RETURN
RETURNS	RETURNS	RETURNS
REVOKE	REVOKE	REVOKE
RIGHT	RIGHT	RIGHT
	ROLE
ROLLBACK	ROLLBACK	ROLLBACK
	ROLLUP	ROLLUP
ROUTINE	ROUTINE
	ROW	ROW
ROWS	ROWS	ROWS
	SAVEPOINT	SAVEPOINT
SCHEMA	SCHEMA
	SCOPE	SCOPE
SCROLL	SCROLL	SCROLL
	SEARCH	SEARCH
SECOND	SECOND	SECOND
SECTION	SECTION
SELECT	SELECT	SELECT
	SENSITIVE	SENSITIVE
SESSION	SESSION
SESSION_USER	SESSION_USER	SESSION_USER
SET	SET	SET
	SETS
SIGNAL	SIGNAL	SIGNAL
	SIMILAR	SIMILAR
SIZE	SIZE
SMALLINT	SMALLINT	SMALLINT
SOME	SOME	SOME
SPACE	SPACE
SPECIFIC	SPECIFIC	SPECIFIC
	SPECIFICTYPE	SPECIFICTYPE
SQL	SQL	SQL
SQLCODE
SQLERROR
SQLEXCEPTION	SQLEXCEPTION	SQLEXCEPTION
SQLSTATE	SQLSTATE	SQLSTATE
SQLWARNING	SQLWARNING	SQLWARNING
	START	START
	STATE
	STATIC	STATIC
		SUBMULTISET
SUBSTRING
SUM
	SYMMETRIC	SYMMETRIC
	SYSTEM	SYSTEM
SYSTEM_USER	SYSTEM_USER	SYSTEM_USER
TABLE	TABLE	TABLE
		TABLESAMPLE
TEMPORARY	TEMPORARY
THEN	THEN	THEN
TIME	TIME	TIME
TIMESTAMP	TIMESTAMP	TIMESTAMP
TIMEZONE_HOUR	TIMEZONE_HOUR	TIMEZONE_HOUR
TIMEZONE_MINUTE	TIMEZONE_MINUTE	TIMEZONE_MINUTE
TO	TO	TO
TRAILING	TRAILING	TRAILING
TRANSACTION	TRANSACTION
TRANSLATE
TRANSLATION	TRANSLATION	TRANSLATION
	TREAT	TREAT
	TRIGGER	TRIGGER
TRIM
TRUE	TRUE	TRUE
	UNDER
UNDO	UNDO	UNDO
UNION	UNION	UNION
UNIQUE	UNIQUE	UNIQUE
UNKNOWN	UNKNOWN	UNKNOWN
	UNNEST	UNNEST
UNTIL	UNTIL	UNTIL
UPDATE	UPDATE	UPDATE
UPPER
USAGE	USAGE
USER	USER	USER
USING	USING	USING
VALUE	VALUE	VALUE
VALUES	VALUES	VALUES
VARCHAR	VARCHAR	VARCHAR
VARYING	VARYING	VARYING
VIEW	VIEW
WHEN	WHEN	WHEN
WHENEVER	WHENEVER	WHENEVER
WHERE	WHERE	WHERE
WHILE	WHILE	WHILE
	WINDOW	WINDOW
WITH	WITH	WITH
	WITHIN	WITHIN
	WITHOUT	WITHOUT
WORK	WORK
WRITE	WRITE
YEAR	YEAR	YEAR
ZONE	ZONE