Reasons to Drop a Secondary Index
There are several reasons you might want to drop a secondary index:
When this happens, you not only waste storage resources by retaining the index, but you also impact system performance by maintaining it.
After the MultiLoad operation completes, you can then recreate the index.
When you encounter this issue, it can be more high-performing to drop the index, perform the maintenance or update task, and then recreate the index afterward because in many cases, it is more efficient to recreate an index than it is to update it in parallel with the updates made to the base data table or join index on which it is defined.