All this talk about DataBases

Scott Kane scott at cdroo.com
Wed May 30 00:42:18 EDT 2007


From: "J. Landman Gay" <jacque at hyperactivesw.com>

> They didn't; the engine has always worked that way since its original 
> MetaCard incarnation. Scott Raney, the creator, wanted speed and so wrote 
> the engine to load everything into RAM. The trade-off is that you need as 
> much RAM as the size of your stack -- which is one reason why a dedicated 
> database is more suitable for huge data sets.

Ah - I see.  Got it.

> Raney's standard suggestion was that databases larger than 5,000 cards 
> should be moved to a "real" external database. Stacks under that number 
> perform acceptably well. I have pushed it to 10,000 or so without any 
> particular indexing or special efforts, but it does slow down, especially 
> if you use the "find" command to locate content. HyperCard had its 
> wickedly fast "hint bits" search that Rev doesn't have. When Rev searches, 
> it has to look through the text of every field which is much slower. 
> However, if you create an index and the scripts reference cards by ID (the 
> fastest way) you can increase the number of cards without too much lag.

Interesting.

> I wrote a database with over 40,000 records, and for that one I loaded a 
> text file into RAM and then used a 1-card display stack to show the 
> desired record. This method requires that you write all your own 
> navigation and search handlers, but it was about as fast as HC when I was 
> done.

Was this on a Windows box though?  My experience with large text files on 
Windows has been that it can really choke.  IIRC this is different under 
*nix style OS'.

Scott Kane
CD Too - Voice Overs Artist  & Original Game and Royalty Free Multi-Media 
Music
"When a distinguished but elderly scientist states that something is 
possible, he is almost certainly right. When he states that something is 
impossible, he is very probably wrong."
Arthur C Clarke 




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