In local there is no IDMS System running above the DBMS. It’s the more efficient mode but lacks the recovery and integrity facilities of the central version (CV) control program. In CV many application programs access the database through a... Read More

They communicate via service MVS request calls. Read More

A page is the smallest unit of storage in an IDMS database Read More

An OOK-Rec is a one of a kind record set, used to get to another record set . Read More

Calc is based on a symbolic value which is used to determine the target page. Via mode is for members only. Via records are stored near to their owners. In direct mode the target is specified by the user and is stored as close as possible to that... Read More

A set is an owner record and, optionally, its member records. There are three types of pointers: next, prior and owner, but only next is required. There are five possible orders for arrangements of sets; they are: first - insert at beginning, last -... Read More

No. The mode is specified via the SYSCTL DD card in the JCL. Read More

The READY prepares a database area for access by DML functions. Read More

A run-unit is a logical unit of work; it is analogous to a CICS task. Read More

Currency is the location within the database during run-unit execution. There are four levels of currency: current of run-unit is the record occurrence of the last successful find or obtain; current of record type is for the most recent of each... Read More

The schema is the physical arrangement of the data as it appears in the DBMS. The subschema is the logical view of the data as it appears to the application program. Read More

IDD is the Integrated Data Dictionary. It contains information about the elements, record types, sets, maps and dialogues within the database. Read More

It generates a bind run-unit and binds all the records for the sub-schema the program is referencing. Read More

Region is used synonymously with area. It is a group of logically contiguous pages. Read More

A record occurrence is the instances of a record; it is the smallest addressable unit of data. A type is the description of a record; there needn’t be any occurrences. Read More

A junction record is a member record type that allows for many-to-many relationship between its two owner records. Read More

It writes a checkpoint to the Journal File and releases any record locks. Read More

It rolls back (reverses) all database updates to the point of the last rollback or to the beginning of the run-unit. Read More

0307 is end-of-set and 0326 is record not found. Read More

Autostatus is a protocol mode which causes the expansion of each DML statement to include a ’perform IDMS-Status’ statement. Read More

It places a record in the database based on the location mode specified. Read More

It will connect to all sets where it is defined as an automatic member. The store requires that currency be established for all these set occurrences. Read More

Store the record then connect it to each set where it is a manual member. Read More

IDMS uses record locks to prevent another run-unit from updating the same record. Read More

Locks may be shared or exclusive. Shared means that other run units can retrieve the record but can not modify it. Exclusive means that other run units can neither retrieve nor modify it. Recordlocks may be implicit or explicit. Implicit locks are... Read More

Locks are released by a change in currency or by a commit, rollback or finish command. Read More

nn29 means that two run units are waiting to set locks on the same record and are in deadlock. Read More

An area sweep accesses records on the basis of the physical location in a database area. It can be total, meaning a record by record search of the area, or it can be of occurrences of records of a specific type. Read More

You are current on the owner. Read More

No difference. There is a difference between obtain first and obtain next for an area sweep, but not when current on the owner in a set. Read More

It releases all database resources, terminates database processes, writes statistical information to IDMS and logs the checkpoint. Read More

Mandatory and optional. Read More

Find tells you whether the record is actually in the database. If it is not found you save the overhead of an obtain. Read More

A bind associates record types with the program work area; for run unit and records it is the first command issued in the program. Read More

Erase cancels the membership of a record in specific set occurrences and removes only the named record. Erase permanent removes the specific record and all mandatory occurrences it owns. It disconnects all optional members. Erase selective... Read More