Hi
PCL4 is not a cluster, at least on Ehp6 at DB level it is a transparent table, that means that the table does exist at both SAP & DB level.
There is a way to process deletion faster, at least for Oracle (but it could also work for other DB)
Create a new temporary table table with a CTAS command (copy table as select) to only include the data for the clients you want to keep.
You can then drop the original table and rename the temporary table to the original name.
Watch out CTAS does not copy indexes, constraints and default values.
If you are using Oracle DB datapump query parameter can be the best option.
You could export the data for the client you want to keep (setting a "query" option like query=" where MANDT in ('200', '300')") , truncate the table and import back the data.
The point here is that copying / inserting new records is faster than deleting.
Regards