Re: Do null columns take up space?

Mike Segel wrote: > > Benjamin Taub wrote: > > > > When using the ONLINE engine (current version), if a column contains a null, will it > > take up bytes in the record? The datatypes of the columns I'm interested in are all > > numeric. I believe that Oracle's engine will compress its tables by assigning no > > storage space to these nulls but I'm not sure how Informix handles this. > > No, sorry no compression. > > From what I remember, and please keep in mind I do suffer > from alzhimers ..... I know, I know, the doctor said you had cancer and alzhimers, and you said 'at least I don't have cancer!' > Informix has kept the table records fixed length. This allows for > faster seek, and fetch times. I am pretty sure this is true for > the standard engine, and I thought it would be true for the > Online stuff as well. Don't forget VARCHAR, TEXT and BYTE. These are all variable length but only available in OnLine. > Another thing to consider. If I have a variable length record and > I update it increasing the size of the record, then how do I store it? I thought about explaining 'home pages', 'remainder pages' and 'big remainder pages'. Then I thought, my waste the space. Still... it's the thought that counts, right? Cheers, -- Mark. +-------------------------------------------------------------------------+ |Mark D. Stock - The West Solutions Group http://www.west.co.za | | | |Email: marks@west.co.za +------------------------------------------------+ |Tel: +27 11 803 2151 |If it doesn't work... force it! | |Fax: +27 11 803 2189 |If it breaks... it needed replacing anyway! | |Cell: +27 83 250 2325 |Well, that's how I code anyway! | +------------------------+------------------------------------------------+