Re: Fwd: avoiding use of Nulls

2009-03-14 Thread michael
Think! I'm not talking about how you application is designed. If your applications allows an employee to be entered without a position in the company, it is a bad design. If a manager at my company hired someone, and did not know what work the new-hire would be doing, well I'd really need to ask

Re: avoiding use of Nulls (was: The = operator)

2009-03-14 Thread Ray
snip I agree with most everything you said, as far as the use of a RDBMS, and especially: quoting you, theoretically you break up your data into tables so that there is never a non-applicable field for any given row. Here is where I disagree with you, and please DON'T take this as an

Re: Getting single results per (left) record with INNER JOIN

2009-03-14 Thread Arthur Fuller
Won't a simple LIMIT 1 do what you want? Or am I missing something? Arthur On Fri, Mar 13, 2009 at 3:24 PM, Nigel Peck nigel.p...@miswebdesign.comwrote: Nigel Peck wrote: SELECT `People`.`person_id`, `People`.`name` FROM `People` INNER JOIN `Person_postal_addresses` ON

Re: avoiding use of Nulls (was: The = operator)

2009-03-14 Thread Claudio Nanni
Hi everybody I want to join as well. But hypothetically speaking, what value would you use if you didn't have a I don't what this is value like null? I ask this because I started programming when NULL was really zero, and part of the ASCII collating sequence. NULL was zero I'd use

Re: avoiding use of Nulls (was: The = operator)

2009-03-14 Thread Morten
I certainly appreciate this discussion and the clear opinions of Mike. Somehow it turned my somewhat simple question into something much more interesting. I believe in referential integrity, I also believe that enforcing a fully saturated data model like Mike proposes, is a constraint on

Re: avoiding use of Nulls (was: The = operator)

2009-03-14 Thread Mattia Merzi
2009/3/13 mich...@j3ksolutions.com: I have a database logging weather data. When a station does not report a temperature, it is set to NULL. It would be a very bad idea to set it to 0 as this would ruin the whole statistics. NULL is a perfectly valid information in many cases. I'd use

Re: avoiding use of NullsA

2009-03-14 Thread Michel Durand
It seems that someone got bitten very hard in a soft area by a Null one day. On a more practical level, Oracle recommended to design the table with the field where NULLs are to be expected at the end of the table, that saves a little space and two, as the use of indexes is invalidated in case

mysql vs fedora-kde-akonadi Q

2009-03-14 Thread Gene Heskett
Greetings; I'm an absolute newbie at databases. Originally I installed mysql because it was needed by mythtv, and with a lot of help I got that to work, although mythtv itself is yet another story. Then I messed up x and was forced to upgrade from my fedora 8 install to fedora 10. Then I

what will happen if the disk is full when mysql flush binlog to it

2009-03-14 Thread Cui Shijun
hi, What will happen if the disk is full when mysql flush binlog to it? If I use innodb engine(mysql-5.1.22) and turn on the binlog, is there any chance that mysql has data updated without binlog flushed? Will mysql return with fail when it fail on binlog? Thank you. -- MySQL General

Re: avoiding use of Nulls (was: The = operator)

2009-03-14 Thread michael
Claudio Nanni wrote: Hi everybody I want to join as well. The question is: Will I allow a record to contain a 'non-informative' field ? No! thats not the question! [a] Ok, go ahead. [b] No, set the field as NOT NULL If you choose [b] please assume your responsibilities. Everytime you

Re: Getting single results per (left) record with INNER JOIN

2009-03-14 Thread Nigel Peck
Arthur Fuller wrote: Won't a simple LIMIT 1 do what you want? Or am I missing something? Thanks for getting back to me. You're missing something, but I probably didn't explain very well. There can be multiple matches from the People table, but when more than one address matches, I get more

Re: Fwd: avoiding use of Nulls

2009-03-14 Thread Johan De Meersman
It's a good thing, then, that we've got your experience to rely on. Woe is us, for not having any, and not seeing how obviously right you are. You're entitled to your opionion on NULLs, but kindly stop spamming *my* mailbox with it. I was aware of your dislike for them after the first mail. On

Re: Getting single results per (left) record with INNER JOIN

2009-03-14 Thread Johan De Meersman
Either HAVING, or an additional GROUP BY field of person_postal_address.person_id should do, I think. On Sat, Mar 14, 2009 at 8:38 PM, Nigel Peck nigel.p...@miswebdesign.com wrote: Arthur Fuller wrote: Won't a simple LIMIT 1 do what you want? Or am I missing something? Thanks for getting

Re: Fwd: avoiding use of Nulls

2009-03-14 Thread Chris W
Arthur Fuller wrote: Exactly the point. Michael, NULL *is* information. It means unknown and that is in itself useful information. A common example: A new employee is hired but which department she will work in is unknown. So the data entry person enters all the known information and leaves

Re: Getting single results per (left) record with INNER JOIN

2009-03-14 Thread Nigel Peck
Johan De Meersman wrote: Either HAVING, or an additional GROUP BY field of person_postal_address.person_id should do, I think. That's great, thanks, just what I needed :) -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: