I am just going through the popular databases IMS DB and DB2. I am recommending to read some popular blogs on these. It improves your knowledge and, if apply it your skills will improve.

https://srinimf.com/2015/06/02/rollup-or-sub-total-in-db2-v11-sql/

Top Blogs

• DB2 Blogs
• Mainframe-Srini Blogs (has all mainframe technologies information)
• IMS DB Blogs

In my next posts I would like to give solutions for Mainframe difficult questions…..until then bye…