There have been some questions on that lately in this forum, and I'm also stuck with some limitations, and the 12.0.1 help is rather quiet on this facility...

And I guess I think I remember I have once seen several samples in the newsgroups, possibly in an answer by Mark. Unfortunately, even Google couldn't help to find them (if they have been published i>anywhere).

IMHO, what is really missing in the docs are topics like:

• Samples to INSERT, UPDATE, DELETE from proxy tables on DASs
• Can I use an environment variable within the CREATE SERVER definition, such as %TEMP%? - In my tests, no.
• Can I use anything else as a "file_name = " condition to INSERT/UPDATE/DELETE files? - In my tests, no - even "file_name like" seems to fail
  And if not, how to use cursor loops to use other conditions?
• Can I use INSERT ... SELECT to copy files between two DASs? - Seems to work
• Can I use all fields to insert/update the proxy tables, or are some fields "computed"? - Apparently, specifying unfitting values for contents and size might lead to problems...
• How to debug such access? - Setting CIS_OPTION = 7 is not too helpful here, methinks, in contrast to other server types.
• Should I copy the contents via querying/inserting the contents field, or is using xp_read_file/xp_write_file the preferred method?

In my tests (with 12.0.1.3726 on Windows XP), directory access servers seem rather different to handle in contrast to other remote access servers, and that should be documented better.

If there's a whitepaper or the like, I'd like to get to know:)