hello

Since NetExpress was published, 30 years ago, whenever I have had to create an indexed sequential file, in a NE application managed through .app projects, it has always generated 2 files (IDX for indexes and DAT for data). It will be that by default it is configured with the IDXFORMAT(3) directive.

My experience has been very good, and it has helped me with the Rebuild tool, to solve any incident and data recovery.

You can set the IDXFORMAT"8" directive either as the default for all indexed files or for specific files only by using the $SET IDXFORMAT"8" before the file's SELECT statement in the source or within an extfh.cfg file.

The default format for indexed files in a NE application is IDXFORMAT=3, you have nothing to do for that.

As Chris has written, you can have another format IDXFORMAT=8 which has no separate physical file for the index.
I am using this format for very big files, which can grow up over 2 GB. If i remember right 2 GB is the maximum size for IDXFORMAT=3 files.

I prefer to define this format in a extfh.cfg file. The advantage is, this applies to the whole application and you must not change anything in your programs.
To convert an existing file from IDXFORMAT=3 to IDXFORMAT=8 you can use the rebuild tool.

thanks for your answer. I use since over 25 years only mssql database for access files, before i had use also sequential, relative and index-sequential files.

Here i want to read the project.app (idxformat(8) for documentation purpose only. And i am near a result, see also the visual coobl forum.

have a nice day