Characters

The basic symbols of keywords and operators in the SQL language are single-byte characters⁷ that are part of all character sets supported by the IBM relational database products. Characters of the language are classified as letters, digits, or special characters.

A letter is any of the 26 uppercase (A through Z) and 26 lowercase (a through z) letters of the English alphabet. ⁸

A digit is any of the characters 0 through 9.

A special character is any of the characters listed below: ⁹

	space	-	minus sign
"	quotation mark or double-quote	.	period
%	percent	/	slash
&	ampersand	:	colon
'	apostrophe or single quote	;	semicolon
(	left parenthesis	<	less than
)	right parenthesis	=	equals
*	asterisk	>	greater than
+	plus sign	?	question mark
,	comma	_	underline or underscore
| 10	vertical bar

⁷

Note that if the SQL statement is encoded as UCS-2 data, all characters of the statement except for string constants will be converted to single-byte characters prior to processing. Tokens representing string constants will be processed as UCS-2 graphic strings without conversion to single-byte.

⁸

Letters also include three code points reserved as alphabetic extenders for national languages (#, @, and $ in the United States). These three code points should be avoided because they represent different characters depending on the CCSID.

⁹

The not symbol (¬) and the exclamation point symbol (!) are also special characters used by DB2 UDB for AS/400. You should avoid using them because they are variant characters.

¹⁰

Using the vertical bar (|) character might inhibit code portability between IBM relational database products. It is preferable to use the CONCAT operator instead of the concatenation operator (||). Use of the vertical bar should be avoided because it is a variant character.