What is IMS GNP?
A GNP with a qualified SSA describes to IMS the segment you want retrieved or the segment that is to become part of the hierarchic path to the segment you want retrieved. A qualified GNP describes a unique segment only if it is qualified on a unique key field and not a data field or a non-unique key field.
What is the difference between GN and GNP?
The difference between a GN and a GNP is that GNP limits the segments that can satisfy the call to the dependent segments of the established parent. An unqualified GNP retrieves the first dependent segment occurrence under the current parent.
What is GN call in IMS DB?
A Get Next ( GN ) call is a request for a segment, as described by the SSA you supply, that is linked to the call that was issued prior to the GN call. IMS starts its search at the current position. When you use the GN call: Processing moves forward from current position (unless the call includes the F command code).
What is Gu IMS?
The Get Unique ( GU ) call is used to directly retrieve segments and to establish a starting position in the database for sequential processing. The Get Hold Unique ( GHU ) is the hold form for a GU call.
What are the characteristics of IMS batch environment?
The IMS batch environment consists of a batch region (a single address space) where an application program and IMS routines reside. The batch job that runs the batch environment is initiated with JCL, like any operating-system job. There are two types of IMS batch environments: DB Batch and TM Batch.
What is PATH call in IMS?
Path calls are used to retrieve/ update an entire path of the hierarchy. Sometimes these can be used to retrieve/update the portion of a path. A path call is requested by using the Command Code ‘D’.
What are some examples of GNP?
For example, Ford, an American company, manufactures and sells its motor vehicles throughout Europe. In 2019, Ford sold close to 1 million motor vehicles. Although these vehicles are made in Ford’s European factories, they fall under GNP.
What is DL in IMS DB?
Data Language Interface (Data Language/I, DL/I, Data Language/Interface, Data Language/One) is the language system used to access IBM’s IMS databases, and its data communication system. In any full-function IMS database, the smallest element that can be retrieved is a segment.
How can I retrieve data from IMS database?
With Extract (option 3.3), you can extract all or selected segments from an IMS database, and save them to a sequential data set. After extracting the segments, you can use Load (option 3.4) to load them into another IMS database.
What is Gu call?
What are the characteristics of IMS?
The main features, functionalities and advantages of IMS
- The main features, functionalities and advantages of IMS.
- Search options.
- Right mouse and double click search options.
- Data exporting.
- Object reminders.
- History.
- Business rules and validation checks.
- Naming convention standards.
What’s the difference between Gu, GN, and GNP?
GU – It is dynamic fetching a record from IMS DataBase.Once the call over if you try to give one more GU call , the search will start from ROOT segment . This is the drawback of more then one GU call in one program. GN -It is sequential fetching .
How does an unqualified GN work in IMS?
An unqualified GN call moves up one level in the database hierarchy to fetch the segment. End of database is reached and segment not found. An unqualified GN call tries to fetch a segment of a particular type other than the one just retrieved but stays in the same hierarchical level. Command codes are used with calls to fetch a segment occurrence.
How does Gu call processing work in IMS?
GU call processing is based on the unique key fields supplied in the call statement. If we supply a key field that is not unique, then DL/I returns the first segment occurrence of the key field. The above example shows we issue a GU call by providing a complete set of qualified SSAs.
How is Gu dynamic fetching from IMS database?
GU – It is dynamic fetching a record from IMS DataBase.Once the call over if you try to give one more GU call , the search will start from ROOT segment . This is the drawback of more then one GU call in one program.