RE: Column Defualts

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Also note that many databases calculate the maximum allowable rowsize and allocate that much space whether it's populated or not. This is especially evident when you use char types verses varchar types. It's actually a good thing in most cases that they do, since it allows query algorithms to be more efficient when jumping to the next row is always the same distance and forces records to be stored sequentially. I'd trade disk space for performance any day...

<>< Ryan

-----Original Message-----
From: Ryan Jameson (USA) 
Sent: Tuesday, October 29, 2002 10:30 AM
To: php-db
Subject: RE:  Column Defualts


No, I believe all databases have an isnull bit flag to go with any column stored. So whether you set it or not the bit is being used.

<>< Ryan

-----Original Message-----
From: Gerard Samuel [mailto:gsam@trini0.org]
Sent: Tuesday, October 29, 2002 9:47 AM
To: php-db
Subject:  Column Defualts


Is defaulting a column to NULL considered as a waste of space??
I have a table that has 2 columns (so far) that defualt to NULL, and 
potentially,
there can be good amount of rows with NULL.  Just wondering...

-- 
Gerard Samuel
http://www.trini0.org:81/
http://dev.trini0.org:81/



-- 
PHP Database Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php


-- 
PHP Database Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php


-- 
PHP Database Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php



[Index of Archives]     [PHP Home]     [PHP Users]     [Postgresql Discussion]     [Kernel Newbies]     [Postgresql]     [Yosemite News]

  Powered by Linux