[REBOL] Re: Handling very large databases
From: pa:russo:perd at: 19-May-2001 19:21
>Hi,
> I'm probably missing something obvious here, but anyway: say I have a
>file containing a meg or so worth of
>
>[string! date! integer! string! ...] [string! date! integer! string! ...] ...
>
>and I need to display blocks 120 to 135. Loading the whole file into memory
>just for a few blocks in the middle of the file is obviously a waste of
>time and resources. As this is a cgi script, and my hoster gets a but
>steamed if scripts lock up the system for too long, I would like to optimise
>this case so that I can just load the blocks I need, say something like
>
>projectdata: loadrecords/start/end project-datafile 120 135
>
>Is there a way I can do this?
>
>Chris
Hi Chris,
You can find some useful tips on "REBOL/Core User Guide 2.3".
This is the beginning of the "Ports/Other Port Modes/Direct Port
Access" section:
...The /direct refinement opens an unbuffered port. This is useful
to access files a
portion at a time, such as when a file is too large to be held in memory....
.
An example follows.
You'll find only sketchy informations, but it's a start.
HTH
--
Paolo Russo
[pa--russo--perd--com]
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