Indexes again

  Sorry, I'll remake (rewrite? redo? ... bad English :/ ) my question:

  I have Books, Authors and Intermediate table. At intermediate I'm
currently using the following indexes:

  CREATE INDEX authorIndex ON Intermediate(author_id);
  CREATE INDEX bookIndex ON Intermediate(book_id);

  I need a third index to not allow duplicated data in my table:

  CREATE UNIQUE INDEX blablabla ON Intermediate(author_id, book_id);

  I'd like to know if, using the third index I can delete one of the
first. Maybe both?

  Thank you! Bye!


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Silas Justiniano - Brazil