Table of Contents
How do I increase my GDG limit?
If you use the access method services ALTER command to increase the GDG limit, no rolled-off GDSs or deferred roll-in GDSs are rolled in. When you increase the GDG limit, you must use the ALTER ROLLIN command to roll in the rolled-off generations if you need to access them.
What will occur in a GDG when the limit is exceeded?
The explanation provided by the Storage Management Team is that, since the number of GDG’s had exceeded the LIMIT, the older generations had rolled-off, and had been archived.
How many generations are possible under a GDG?
The maximum number of host GDG generations that you can reference is 255. MSS does not support versioning of the GDG generations, so the only generations that versioning works for are those with a data set name ending with V00.
How do I find GDG base information?
How to see and read the properties of a GDG?
- In the ISPF command line, you can issue a command ‘TSO LISTC ENT(‘GDG-BASE-NAME’) ALL’
- Use LISTCAT ENTRY ‘GDG-NAME’ ALL in the IDCAMS utility of the JCL.
- Use a utility called Fileaid if your site supports Fileaid.
What is NoEmpty and scratch in GDG?
scratch : It will scratch the older versions of the GDG, giving space for the newer versions. Empty : It will empty the GDG versions. NoEmpty : It will not empty the GDG versions, rather it will delete the older versions of the GDG.
How can we retain two versions of a single GDG generation?
You can catalog a new version of a specific generation automatically by specifying the old generation number along with a new version number. For example, if generation A.B.C. G0005V00 is cataloged and you now create and catalog A.B.C. G0005V01, the new entry is cataloged in the location previously occupied by A.B.C.
What is scratch and Noscratch in GDG?
Noscratch : It will not delete the GDG versions when the max number of versions for the GDG is reached. scratch : It will scratch the older versions of the GDG, giving space for the newer versions. Empty : It will empty the GDG versions.
What happens if you use +2 in GDG without 1?
Suppose, you have given (+2) in JCL instead of (+1), then, it creates (+2) generation. So, it jumps the generation number to 2. Usually, it should be (+1). Since you have given as (+2), it creates (+2) generation after (0) generation.
What is the range of the limit parameter in GDG?
LIMIT specifies that the maximum number of GDGs in the group is 255.
How can I check GDG base properties?
How do I read a GDG dataset?
How many datasets can be concatenated in JCL?
Concatenating Datasets If there is more than one dataset of the same format, they can be concatenated and passed as an input to the program in a single DD name. In the above example, three datasets are concatenated and passed as input to the SORT program in the SORTIN DD name.
How can I create multiple GDG versions in JCL?
GDG versions: In JCL, always (0) version states that the current version. If you want to create another generation, you need to give GDG(+1). Even, you use the same dataset as input, in downstream steps, you need to give as (+1). So, this states that it creates next to the current generation.
What are the parameters used for creating GDG?
Its parameters are: NAME specifies the name of the GDG, GDG01. Each GDS in the group will have the name GDG01. GxxxxVyy, where xxxx is the generation number and yy is the version number.
How many sequential data sets can be concatenated together?
The system can retrieve two or more data sets and process them successively as a single sequential data set. This is called sequential concatenation.
What is scratch in GDG?
What happens when dataset is uncataloged?
If you select option U, the specified data set name is uncataloged. There is no need for the specified data set to be allocated or for the volume on which it resides to be mounted. If the catalog entry being removed contains an expiration date in the future, a confirmation panel is displayed.
How do I increase the GDG limit for GDSs?
If you use the access method services ALTER command to increase the GDG limit, no rolled-off GDSs or deferred roll-in GDSs are rolled in. When you increase the GDG limit, you must use the ALTER ROLLIN command to roll in the rolled-off generations if you need to access them.
What happens when you increase the GDG limit in access method services?
If you use the access method services ALTER command to increase the GDG limit, no rolled-off GDSs or deferred roll-in GDSs are rolled in. When you increase the GDG limit, you must use the ALTER ROLLIN command to roll in the rolled-off generations if you need to access them. In contrast, GDSs are immediately rolled off if you decrease the limit.
What is the difference between GDG and GDS?
When you increase the GDG limit, you must use the ALTER ROLLIN command to roll in the rolled-off generations if you need to access them. In contrast, GDSs are immediately rolled off if you decrease the limit.
How many generations of data can A GDG handle?
Finally, this example of a GDG was created with 15 generations of data sets using the LIMIT (15) parameter. If you wish to change the number of generations run this IDCAMS alter example where the number of generations is increased to 50.