Levels of data sharing
DBRC supports the two levels of IMS data sharing: database level and block level.
- Database level
- The entire database or DEDB area is a resource that can be accessed for update by a single IMS system at a time. For area resources this can also be called Area-level sharing.
- Block level
- A database or DEDB area can be accessed by multiple IMS subsystems concurrently. Data integrity is preserved for the IMS subsystems that access the shared data. Within a database or area, resources are reserved at the block level.
Definition: For OSAM databases, the
block is a physical data block stored on DASD. For VSAM databases
and DEDBs, the block is a control interval (CI).