Multiple indexes for one field - why is this possible?

Question

MySQL

Is there any sense in this, and if not, why is this possible?

Answer 1

in this case, it is useless and only aggravates the bet (recalculation of identical indices)
if there was first one index on nicename, and then a composite nicename+id index - this might be necessary (depending on needs)
it is also worth noting, that nicename and nicename_2 indexes are different (one is unique, the other is not unique), you need to choose what is still required,
but the nicename_2, nicename_3, nicename_4, nicename_5 indexes are absolutely the same and this is redundant

Answer 2

They just didn't make foolproof.

Answer 3

In short, this needs to be fixed by the developers.