Inherent limitation of d3/win v9 and possible designbais issues

[David Knight]

Recently I had one of those "this cannot be happening" issues when using designbais, specifically v8 on d3/win v9.x.

I was having weird display issues and other errors when building a form, in this case containing a mv associative input control.

Eventually it turned out the issue was because d3 [unbeknownst to me] has a 100 byte limit on an item key. As an aside, I've asked Rocket to hopefully change that; but it does have a designbais implication.

Many thanks to the usual suspects Jon Legg & Bob Garrard for taking the time to find the issue after my long emails!

db has to maintain state via Session records, specifically written to the DBISESSIONS file. Now the key to those records is almost always complex and contains delimited data about the content of each state record.

The key often contains a session id, and a bunch of other things, in my case including the filename and formname. Now I tend to use fairly verbose names; and not abbreviations; and that caused me to come unstuck because when db wanted to create a record for writing with a complex key containing the session variable and a filename and formname plus some other stuff they needed; the key was > 100 bytes.

Unfortunately, d3 does not warn you what it is going to do with such records; but I can say from my testing the result is at the very least weird!

Therefore, it behooves one to keep filenames and formnames brief to avoid this weird occurrence.

I've suggested to the db folks they document and publish the factors that comprise the range of large compound keys so and what the maximum key size on each incarnation of mv they support; so designers can make informed decisions...

Cheers one and all.

[Jon Legg]

This has come up again with UniData's limit of 125 characters.

UniVerse is 254

Session ID (32 CHARS) + File + Form are the common ID components.

Editor keys have the full file path + session ID.

Some snapshots of common had the file + form mentioned twice - this has been fixed when the same form is repeated. We will probably move snapdhots to simply use the DBWLEVEL.