Case: How To Clean Up Large Table

We have a large interface table with more than 12m records,  unfortunately, most of them are useless, we’d like to clean it up for performance optimization.
Delete useless data by ‘delete from ’  and subsequently shrink the table to lower the HWM?  It’s not a good choice. DBA hates that as delete clause would generate huge log, probably the operation would fail.
Truncate the table? I just can’t do that, some data couldn’t be eliminated now.
Here is the DBA’s suggestion:
Step 1: Select the useful data into a new table table_tmp;
Step 2:  rename the large table  table_origin to table_old;
Step 3:  rename table_tmp to table_origin. Now we have a much smaller table_origin with normal HWM.
Step 4:  Take care of the indices and the privileges;
Step 5:  ensure the table_origin  is healthy and then drop table_old;

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