In a combination of multiple concurrently-executing database management systems which share data storage resources, efficient lock processing for shared data is implemented by hiding from a global lock manager the distinction between transaction-interest and cache-interest locks that are processed at...http://www.google.com.tw/patents/US5551046?utm_source=gb-gplus-share專利 US5551046 - Method for non-hierarchical lock management in a multi-system shared data environment
