Re: Event-based databases

T.M. Sommers wrote:

which are variable length.

I would think that fixed-length fields in the files would improve performance:

Variable:

Read length of field
Read field

Fixed:

Read field

One read instead of two, no calculations, easy to jump to any row in the file, and so on.


Uh, no, in many cases. The first calculation is "is the data in the RAM-memory data cache, or do we need to go to disk to find it?". A smaller total database means that there is a
higher probability that you won't need to go to disk.

Without an in-RAM disk cache, and if the disk file system allows random disk seeks controlled by the program, then that is where the fixed length fields .. and thus locations in disk blocks ... speeds things up.

Doug McDonald
.

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