Further to Martin's splendid explanation of Pick NULL vs SQL NULL (below) there is sometimes some confusion with the statement "NULL".
This has nothing to do with the value(s) NULL but refers to a No-Op statement that can be used when nothing needs to be done but a THEN or ELSE statement is required. Example... LOCATE (X, REC ; POS ; 'AR') ELSE NULL Enjoy! Trevor Ockenden Open Systems Professionals -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Martin Phillips Sent: Monday, 14 February 2005 3:44 AM To: [email protected] Subject: Re: [U2] (ignore last email!) GE and LE question Pick style databases have historically used the term "null" to mean an empty (zero length) character string. When SQL support was added, the developers of UniVerse (etc) were faced with a problem of terminology as SQL uses the term null to mean "has no value". The distinction between Pick null and SQL null is always an exciting one to try to explain to novice users. Pick null is explicitly empty whereas SQL null has no value. In my experience, not very many multivalue applications actually use the SQL null concept. In UV, SQL null is represented by putting a special, configurable value in the data field, usually char(128). This is recognised by the query processor and some program constructs. Any use of the term null in the UV world generally has then Pick meaning unless you make it clear you are talking about SQL null. Hence, the original posting that raised this thread was absolutely right; a null field is an empty string. Martin Phillips Ladybridge Systems 17b Coldstream Lane, Hardingstone, Northampton NN4 6DB +44-(0)1604-709200 ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/ -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.300 / Virus Database: 265.8.7 - Release Date: 10/02/2005 __________________________________________________________________ << ella for Spam Control >> has removed Spam messages and set aside Newsletters for me You can use it too - and it's FREE! http://www.ellaforspam.com -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.300 / Virus Database: 265.8.7 - Release Date: 10/02/2005 ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/
