The Sinclair QL Forum

Can anyone tell me what the limits are for data design (ddf) files?
Specifically:
- How many records can it maintain?
- How many fields can a _ddf file have?

I don't think I've found this information in the documentation, but maybe I haven't looked closely.
Thanks.

Giorgio

It's roughly at the end of the manual, before the PE introduction:

max no of records no limit, except memory (18 bytes/record)
max no of fields 256
max no of files no limit
max no of buffers no limit
max no of indexes no limit
max recordlength only limited by memory
max fieldlength only limited by memory
max no of sortlevels 10
max no of filterlevels 10

Hello
i am working the last 25 years with dd files with 600+ entries
the dd front end is imho just bit clumsy so i did make my own
Greetings from Switzerland
Markus

Great, thank you!

Thanks to everyone for the answers, I am very interested in datadesign, to use it in my accounting programs. I have always used DBAS but now I need a much more powerful database. I have done some research on the forum but found very few messages, so I thought it wasn't used by anyone. Does anyone of you use it regularly? (I am not talking about the program that displays/edits records, I am interested in using it through APIs). I am studying the manual but there are some things I struggle to understand, it's my fault for not being very good at English, I use Google Translate. Can I ask any of you more 'complicated' questions about certain operations that I have trouble understanding?

 
As tofro wrote in another message, SQLite is written in C (correct, verified in Wikipedia), I THINK it should be possible to convert it to the QL with C68 or at least with the GCC QL cross compiler. Than we would have a real SQL database. Someone must of course write machine code SuperBASIC extensions, to access it.

ql_freak wrote: Tue Aug 19, 2025 1:41 am  
As tofro wrote in another message, SQLite is written in C (correct, verified in Wikipedia), I THINK it should be possible to convert it to the QL with C68 or at least with the GCC QL cross compiler. Than we would have a real SQL database. Someone must of course write machine code SuperBASIC extensions, to access it.

While sqlite is still a "lite" database, I'd seriously consider it "too heavyweight" for the average QDOSMSQ machine. sqlite compiled binaries work out to between 750k to close to under 1MB (more to the latter usimg our available compilers), which is definitely out of reach for most of our machines.

ql_freak wrote: Tue Aug 19, 2025 1:41 am  
As tofro wrote in another message, SQLite is written in C (correct, verified in Wikipedia), I THINK it should be possible to convert it to the QL with C68 or at least with the GCC QL cross compiler. Than we would have a real SQL database. Someone must of course write machine code SuperBASIC extensions, to access it.

It could be a nice idea, as soon as you are done send me the software to test

Last night I took a test: I wrote a batch procedure to load data to insert a million records into a _ddf file, I managed to do it in about 15 minutes (Under QPC2).

Giorgio

Giorgio Garabello wrote: Mon Aug 18, 2025 3:15 pmI have done some research on the forum but found very few messages, so I thought it wasn't used by anyone.

I actually only know one program that uses the Datadesign engine, namely "Agenda" by Wolfgang Lenerz. It's a calendar program that lets you manage your appointments.