Bill
I know my app may not be sensibly but I can't think of any code I have that is
giving
us problems.
Off the top of my head I can't think of a place were we compare 2 vars. Most
of what
we do is Where colname = 'Smiht' or Where Phone Contains '1234'
I will double check my code for possible problems.
thanks
Marc
sitting in the back of the class with the pointy hat on
----- Original Message -----
From: Bill Downall
To: RBASE-L Mailing List
Sent: Friday, April 11, 2008 8:23 AM
Subject: [RBASE-L] - Re: EQNULL ON or OFF
Marc,
If you designed your database schema, using NOT NULL constraints sensibly,
and if you program carefully so that you will never be comparing two unknown
values, that go right ahead.
In the SQL standard, if a variable or column is null, then a comparison of
that value with an equal sign should always be false. An unknown value cannot
be equal to any value, not even to another unknown value.
EQNULL is an R:BASE accommodation for people who don't like that part of the
SQL standard.
Bill
On Fri, Apr 11, 2008 at 9:19 PM, Marc <[EMAIL PROTECTED]> wrote:
I always thought of Zero for integer and currency and EQNULL for
text.
I can't think of any problem with having EQNULL ON ?
But it is Friday so I may be overlooking something.
Marc
----- Original Message -----
From: Bill Downall
To: RBASE-L Mailing List
Sent: Friday, April 11, 2008 8:02 AM
Subject: [RBASE-L] - Re: EQNULL ON or OFF
Sorry, Marc, you're right. EQNULL is a little more insidious. It means
that an expression like...
IF myvar = someothervar THEN
... will be evaluated as true if both sides of the operator are null.
Or: "if I don't know this, and I also don't know that, then they must be
the same."
Bill
On Fri, Apr 11, 2008 at 8:55 PM, Marc <[EMAIL PROTECTED]> wrote:
Hi BIll
I thought that was Set Zero On?
Marc
----- Original Message -----
From: Bill Downall
To: RBASE-L Mailing List
Sent: Friday, April 11, 2008 7:47 AM
Subject: [RBASE-L] - Re: EQNULL ON or OFF
Marc,
When EQNULL is on, R:BASE doesn't distinguish a null from a zero, so
any average calculations are screwy.
Bill
On Fri, Apr 11, 2008 at 8:41 PM, Marc <[EMAIL PROTECTED]> wrote:
After reading the other thread I got nervous about my EQNULL
setting.
I have it set to ON, so now I am worried. I had a problem sometime
back
and setting EQNULL ON fixed that problem so I just leave it on.
What are the dangers with it ON?
thanks
Marc
----- Original Message ----- From: "Lawrence Lustig" <[EMAIL
PROTECTED]>
To: "RBASE-L Mailing List" <[email protected]>
Sent: Thursday, April 10, 2008 7:21 PM
Subject: [RBASE-L] - Re: Testing for field diferences.
<<
Interesting thought but I refuse to futz with the EQNULL option.
It is not standard SQL and can have unwanted side effects.
You can do this more or less safely like this:
SET VAR vSaveEQNull = (CVAL('EQNULL'))
SET EQNULL ON
IF <<Condition Here>> THEN
-- Do Stuff
ENDIF
SET EQNULL &vSaveEQNull
CLEAR VAR vSaveEQNull
As long as your confident in the IF statement and the nested
code, this will do what you want without endangering the database wide EQNull
setting.
--
Larr
