Re: NULL values or Zero in numeric fields?

EndUser (enduser_at_enduser.com) wrote:
: the correct opinion, i add.
 

: youd be surprised how many "professionals" dont undertand
: this basic concept.
 

: --
 

: In article <49hske$osj_at_peacock.tcinc.com>, Ron Reidy <rreidy> wrote:
 

: > francois.lachance_at_sasknet.sk.ca (Francois Lachance) wrote:
: > >We have a few tables with numeric columns. By default, if you don't
: > >save a value in those columns, they are NULL values. Is there an
: > >advantage to leaving these empty rows as NULL? Users that are doing
: > >queries directly against the database are asking that Zero be put in
: > >the rows where no value has been specified. Programmers find it
: > >annoying to have to make sure that calculations are not done on NULL
: > >values since it returns a NULL if you do.
: > >
: > >What does that do as far as data storage is concerned? Will a zero
: > >take more space then a NULL?
: > >
: > >Thanks for any help that you can provide.
: > >
: > >
: > >+===================================================================+
: > >+ +
: > >+ Francois Lachance +
: > >+ Data Administrator +
: > >+ Saskatchewan Highways and Transportation +
: > >+ Regina, Saskatchewan +
: > >+ Canada +
: > >+ +
: > >+===================================================================+
: > >
: > >
: > Answers:
: >
: > 1. Yes there is a storage advantage to leaving columns NULL. No space is
: > taken up in the table when a column is NULL.
: >
: > 2. Programmers are correct to not want to put 0's there. A 0 denotes
: > something, NULL denotes absence of something. The difference is subtle, but
: > signficant.
: >
: > 3. End-users need to be trained in the correct use of tools (or special tools
: > bult for them). They will have to learn how the data works and what the
: > significance of it is.
: >
: > Just my opinion, of course.
: >
: > rr
Received on Wed Dec 06 1995 - 00:00:00 CET