Will having same indexes on two tables decrease the performance

Hi
We are having some indexes on five tables.Every month we run a backend process which rename's the existing table to old and drops the existing and creates new tables with indexes.
We wont be referring the old tables in our application but the same indexes will be there still as on new table.
For example TableA--Index_A,Index_B
After her batch process
TableAOld--Index_A,Index_B
TableA--Index_A,Index_B
Only tableA will be used by the application.
Will it affect the performance or only more space will be used becasue of presence of indexes on theOld table.
Could any one answer my question
Please let me know if you have any questions.
Thanks,
Surendra

Hi Surendra,
When you dont use a Table, Obviously the indexes in the table wont be used. The only disadvantage is the wastage of space.