Re: dbase
- Posted by Marcel Kollenaar <M.Kollenaar at SLO.NL> Oct 23, 1996
- 1769 views
Hi Daniel, Daniel Berstein Zimmermann wrote: > Hi Marcel, I'm also interested in databases. I have some expirience > with Clipper 5.2 and other Xbase laguages, which use the standard > .dbf file. By now I'm coding some functions that read and write > .dbf files, and also some utility function for databases: a browse() > function (like browse or dbedit of clipper, based in my menu engine) > and some get() function with "pict" capability, and of course an > indexing system. Thats the point....... > For what I've telled you I have an idea (even some functions are > ready) of what to code, but for indexing (I expect to make it > compatible to Dbase's NDX format or Clipper's NTX format) I just > don't know where to start. I had the same problem. I ask my girl friend where to start. She said: "In the middle." So I did. (No dirty joke gentlemen) I found a study book of Wirth "Data structures" and studied the B+tree section and started to code an tree insert, delete and search function. Made my own file structure and so on. I worked back and forth. I can tell you, If you've seen one you've seen them all. It's one principal easy to understand but huge to code. > If you have some specs of this formats I would be very thankful. I don't have have spec's of NDX, NTX format and I can't find information about it on the net. > I will post these function when they get more > complete. I think it's great we could share our codes, Yes, great I look forward to it. When I get my B+tree code stabilized and it does what it has to do I put it on the listserver. > but some > codes posted in the listserver require tons of patience to > understand their mechanics. I spend lots of time translating to You are right. It takes me also lots of time to study others code. > English (the comments, the function names and the variable names) > so they could be easily understood by everyone (hope), and be a > source of ideas (hope too) >for all. Thanks Daniel for your reply. Keep on coding .... A tip .... David Gay wrote some interesting indexing code to link two databases with common fields. I'm now studying this code and try to use it for an applycation I have in mind. Marcel Kollenaar M.Kollenaar at slo.nl The Netherlands