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OpenEdge SQL identifiers
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Conventional identifiers
Conventional SQL identifiers must:
• Begin with an uppercase or lowercase letter
• Contain only letters (A–Z), digits (0–9), or the underscore character ( _ )
• Not be reserved words, such as CREATE or DROP
• Use ASCII characters only
SQL does not distinguish between uppercase and lowercase letters in SQL identifiers. It
converts all names specified as conventional identifiers to uppercase, but statements can refer
to the names in mixed case.
Example The following example illustrates the use of identifiers in a simple query statement where
CustNum, Order, and OrderDate are the user-specified names of columns:
SELECT CustNum, COUNT(*)
FROM Order
WHERE OrderDate < TO_DATE ('3/31/2004')
GROUP BY CustNum
HAVING COUNT (*) > 10 ;
Delimited identifiers
Delimited identifiers are strings of no more than 32 ASCII characters enclosed in quotation
marks ( " " ). Delimited identifiers allow you to create identifiers that are identical to keywords
or that use special characters (such as #, &, or *) or a space.
Enclosing a name in quotation marks preserves the case of the name and allows it to be a
reserved word or to contain special characters. Special characters are any characters other than
letters, digits, or the underscore character. Subsequent references to a delimited identifier must
also use quotation marks. To include a quotation mark character in a delimited identifier,
precede it with another quotation mark.
The following code example uses a delimited identifier to create a table named "Dealer
Table", where the space character is part of the name:
CREATE TABLE "Dealer Table" (name, address, city, state)
AS
SELECT name, address, city, state
FROM customer
WHERE state IN ('CA','NY', 'TX') ;