delete duplicate records from master table mysql

Question

I have 2 mySQL tables (table Master and table Backup) Some rows are copied to backup table and some not...

Now I need to delete those all rows from Master Table which are availble in Backup table with single query, coz approx. 700k+ rows are in both tables

Answer 1

Something like:

DELETE FROM master_table WHERE id IN (SELECT id FROM backup_table)

Of course it needs unique key on id field to work