>>> How do I figure out when certain files were written to a particular
>>> volume? ...

>>Join the contents of that volume with that data in the Backups and
>>Archives tables.

>Great!
>how do i do that?

Conceptually simple, but as always the devil is in the details.
Via 'Query CONtent' or 'SELECT ... FROM CONTENTS ...' you identify the
files of interest.
If they are Backup files, you then use that data do:
 SELECT * FROM BACKUPS WHERE NODE_NAME='____' AND FILESPACE_NAME='____' AND
  HL_NAME='<The_Directory>' AND LL_NAME='<The_File>'
Similarly for Archive files, in the Archives table.
Be as specific as possible to minimize the database processing.

However...  Unless things have improved very recently, a conspicuous deficiency
in the Contents table is the absence of anything to uniquely identify the
instance of its FILE_NAME, to be able to correlate with the corresponding entry
in the Backups table, as would be possible if the Contents table carried the
OBJECT_ID. The best you can do is try to bracket the files by creation timestamp
as compares with the volume DATE_TIME column from the Volhistory table and the
LAST_WRITE_DATE from the Volumes table.  You might also employ
"STATE='ACTIVE_VERSION'" in the SELECT * FROM BACKUPS to eliminate less-relevant
Inactive files.

  Richard Sims, BU