Query Language Identifier
Query Language Identifier
Identifiers
An identifier is a sequence of one or more characters. The first character must be a valid first
character (letter, $, _) in an identifier of the Java programming language (hereafter in this
chapter called simply "Java"). Each subsequent character in the sequence must be a valid
non-first character (letter, digit, $, _) in a Java identifier. (For details, see the Java SE API
documentation of the isJavaIdentifierStart and isJavaIdentifierPart methods of the
Character
class.) The question mark (?) is a reserved character in the query language and
cannot be used in an identifier.
A query language identifier is case-sensitive with two exceptions:
Keywords
Identification variables
An identifier cannot be the same as a query language keyword. Here is a list of query language
keywords:
ALL
AND
ANY
AS
ASC
AVG
BETWEEN
BY
COUNT
CURRENT_DATE
CURRENT_TIME
CURRENT_TIMESTAMP
DELETE
DESC
DISTINCT
EMPTY
EXISTS
FALSE
FETCH
FROM
GROUP
HAVING
IN
INNER
IS
JOIN
LEFT
LIKE
MAX
MEMBER
MIN
MOD
NEW
NOT
NULL
OBJECT
OF
OUTER
OR
ORDER
SELECT
SOME
SUM
TRIM
TRUE
UNKNOWN
UPDATE
UPPER
WHERE
It is not recommended that you use a SQL keyword as an identifier, because the list of keywords
may expand to include other reserved SQL words in the future.
Full Query Language Syntax
The Java EE 5 Tutorial · September 2007
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