I set up some tables using inav, and they are written to by php. The web programmer who did them left the "nullable" and default null. I have a few tables I write to from s/36e side of things that way also, never an issue.
However I could not read these tables, got a data mapping error. Looking at the file, there are no binary zeros, just plain jane x'40' but it kept saying reason code 19 which deals with null values.
Now I understand there is something (allow null characters) that you can do in CL and in rpgiv? for such but it seemed like to me the problem was that it must "convert" the stuff during read from the x'40' (space) to something else???
I had to export the stuff out, blow the table contents away, change the sql definitions and re-import. It would not "alter" with stuff in the table.
Can someone shed any light. Needless to say, the web programmer won't be marking them as nullable again...