Can some problem exist when creating 2 indexes of the same records?

CREATE UNIQUE INDEX FK_SCEMMES_A ON SCEMMES (IDAC,IDREG,NUMC);
CREATE UNIQUE DESCENDING INDEX FK_SCEMMES_D ON SCEMMES (IDAC,IDREG,NUMC);

I make it because I need values max

select max(m.numc) as numc from scemmes m where ((m.idac=1) and (m.idreg=1))


Best Regards
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|| ISMAEL ||
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