Joined: 17 Dec 2007 Posts: 59 Location: Victoria, BC, Canada
There used to be a product called "IMS DB/DC Data Dictionary" which was used as a repository for the metadata about IMS databases, segments, fields, DBDs and PSBs. I suspect this product may have been withdrawn from marketing by IBM. That said, your shop may still be running this product.
If you are running IMS V12 or V13 and your sysprog has enabled IMS Open Database with the IMS Catalog enabled, then it is possible you have this metadata about your databases stored in IMS Catalog. This feature is very new, so it is doubtful that IMS Catalog is in place, or populated, for you to use.