Database integrity without data sharing support

Without data sharing support, the responsibility for database integrity lies with administration and operations.

These are the two situations where data integrity is not protected:

• In a single z/OS® operating system, with the database JCL specifying a disposition of SHR, multiple IMS online or batch systems executing simultaneously might concurrently access the database without integrity.
• If multiple IMS systems are executing in more than one z/OS operating system, and a database is on shared DASD, those IMS systems can concurrently access the database. This concurrent access cannot be directly controlled by JCL, even when a disposition of OLD is specified.