Discovered in my dusty email archives, information for an undocumented feature from 2009 to provide a server-side mechanism to manipulate the default isolation level for connections issuing dynamic SQL...
Locking and latching are both key mechanisms employed by relational database management systems to ensure data integrity, consistency, and the serialization of resources. In the Db2 for z/OS IRLM manages the locks, but both Db2 and IRLM have internal latches.
A singleton SELECT - is this always the best solution for readability and performance? The article discusses a simple scenario, that shows that a singleton SELECT can result in surprising application behavior if not used properly.