1⟩ What sets will the stored record connect to?
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.
IDMS
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33 IDMS Questions And Answers
2⟩ What is currency in IDMS?
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 record type;
current of record set is the most recent within each set and current of area is within each area.
3⟩ So manual and automatic are the connect options for a set. What are the disconnect options?
Mandatory and optional.
4⟩ Distinguish among erase, erase permanent, erase selective and erase all?
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 removes the record, all mandatory members and all optional members not connected to other sets. It disconnects those that are connected.
Erase all removes the specified record and all the mandatory and optional records it owns.
5⟩ Why would you use find and get rather than an obtain?
Find tells you whether the record is actually in the database. If it is not found you save the overhead of an obtain.
6⟩ If the stored record is not defined as automatic of a set, how can it be stored as a member of the set?
Store the record then connect it to each set where it is a manual member.
7⟩ What is an OOK-Rec in IDMS?
An OOK-Rec is a one of a kind record set, used to get to another record set.
8⟩ What is the difference between local and central version operating modes?
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 single copy of the DBMS.
9⟩ Explain the difference between record occurrence and record type in IDMS?
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.
10⟩ What is a page in IDMS?
A page is the smallest unit of storage in an IDMS database
11⟩ What is a region in IDMS?
Region is used synonymously with area. It is a group of logically contiguous pages.
12⟩ What is a run unit in IDMS?
A run-unit is a logical unit of work; it is analogous to a CICS task.
13⟩ What is the difference between a schema and a subschema in IDMS?
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.
14⟩ What does a store statement do?
It places a record in the database based on the location mode specified.
15⟩ If you are current on the owner of a set, what is the difference between an obtain next and obtain first in IDMS?
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.
16⟩ How does IDMS communicate with CICS?
They communicate via service MVS request calls.
17⟩ Is there a application program coding difference between local and central version mode in IDMS?
No. The mode is specified via the SYSCTL DD card in the JCL.
18⟩ What is a bind in IDMS?
A bind associates record types with the program work area; for run unit and records it is the first command issued in the program.
19⟩ When you are obtaining next within a set and get a end of set return code, on what record are you now current in IDMS?
You are current on the owner.
20⟩ What is an area sweep and when is it used in IDMS?
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.
