Renaming data sets

You can rename data sets with the RENAMEUNCONDITIONAL (RENAMEU) keyword for the COPY command. For VSAM data sets, you can only rename clusters. DFSMSdss derives the new names for the components of VSAM clusters as follows:

If the data set is a linear data set and the new cluster name matches the following convention:
```
     HLQ1.DSNDBC.HLQ3.HLQ4.%nnnn.%nnn
```
and the old component matches the following convention:
```
     HLQ1.DSNDBD.HLQ3.HLQ4.%nnnn.%nnn
```
where % is any single letter, nnnn is a 4-digit number, and nnn is a 3-digit number, then DFSMSdss generates the target component as follows:
- If a qualifier from the source cluster name is identical to the corresponding qualifier of the source component name, the corresponding qualifier from the target cluster name is used in the target component name. Otherwise, DFSMSdss uses the qualifier from the source component name in the target component name.
- DFSMSdss sets the sixth qualifier of the new component name to AD for a data component, or to AI for an index component whenever any of the following conditions are true:
  - The new target component name exceeds 44 characters.
  - The new cluster name and new component name are identical.
  - The old component name and new component name are identical.
- If the standard order of search directs the new target component name to a different catalog with the new cluster name, the following occurs:
  - DFSMSdss regenerates the target component name using the first five qualifiers of the new cluster name.
  - DFSMSdss appends a sixth qualifier of either AD for the data component or AI for the index component.
If the following conditions are true:
- The data set is a linear data set
- DFSMSdss was invoked using the application interface
- The UIM set the EI22DB2 bit ON
- The new cluster matches the following convention:
```
HLQ1.DSNDBC.HLQ3.HLQ4.%nnnn.%nnn
```
  where % is any single character, nnnn is a 4-digit number, and nnn is a 3-digit number.
then DFSMSdss generates the target component name by using all of the qualifiers of the new cluster name as the corresponding qualifiers of the target component name, with the exception of the second qualifier. The second qualifier of the target component will be "DSNDBD."
If the old component's name is equal to the old cluster name (plus any suffix), then the new component name will equal the new cluster name, plus the same suffix of the old component.

Example: When RENAMEU(NEW) is specified, the following configuration occurs:
Instance Cluster Name Data Component Name Index Component Name
Old IBM.DFSMS.DSS IBM.DFSMS.DSS.DAT1 IBM.DFSMS.DSS.INDX1
New NEW.DFSMS.DSS NEW.DFSMS.DSS.DAT1 NEW.DFSMS.DSS.INDX1
If the old and new cluster names have "cluster" as their last qualifier, and the old component names match the cluster name up to the last qualifier, then the new component names will adhere to the old component naming convention.

Example: When RENAMEU(SYS2) is specified, the following configuration occurs:
Instance Cluster Name Data Component Name
Old SYS1.IODF00.CLUSTER SYS1.IODF00
New SYS2.IODF00.CLUSTER SYS2.IODF00
If the last qualifier of the new cluster name is "cluster," and the old component names do not match the cluster name up to the last qualifier, then new component names will be generated using the new cluster name and replacing the last "cluster" qualifier with "data" or "index."

Example: When RENAMEU(SYS2) is specified, the following configuration occurs:
Instance Cluster Name Data Component Name
Old SYS1.IODF00.CLUSTER SYS1.DFSMS
New SYS2.IODF00.CLUSTER SYS2.IODF00.DATA
If the new cluster name is less than or equal to 42 characters and the last qualifier is not "cluster", DFSMSdss creates component names by adding a single character to the new cluster name: "D" for the data component, "I" for the index component.

Example: When RENAMEU(SYS2) is specified, the following configuration occurs:
Instance Cluster Name Data Component Name
Old SYS1.IODF00.DATASET SYS1.DFSMS
New SYS2.IODF00.DATASET SYS2.IODF00.DATASET.D

If renaming the data set results in a component name that exceeds 44 characters in length, DSS replaces any DATA or INDEX specific qualifier with ''D'' or ''I'' respectively.

Example: When RENAMEU(NEWNAM) is specified, the following configuration occurs:

Instance	Cluster Name	Data Component Name
Old	`IBM.DFSMS.DSS.LARGE.VSAM.DSNAME.TEST`	`IBM.DFSMS.DSS.LARGE.VSAM.DSNAME.TEST.DATA`
New	`NEWNAM.DFSMS.DSS.LARGE.VSAM.DSNAME.TEST`	`NEWNAM.DFSMS.DSS.LARGE.VSAM.DSNAME.TEST.DATA`

If the new cluster name is more than 42 characters and the last qualifier is not "cluster," DFSMSdss derives the component names by doing the following:
- Using up to the first four qualifiers of the new cluster name
- Appending eight-character qualifiers, generated by using the time clock and system date, until the component names are five qualifiers
Using up to the first four qualifiers of the new cluster name ensures that the component names will orient to the same catalog as the cluster.

Note: These examples represent common renaming scenarios. A combination of renaming rules might apply, depending on the source and target names of any given cluster or component.