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From:Martijn Tonies Date:October 3 2005 10:29am
Subject:Re: Double indexes on one field
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> Using PhpMyAdmin, I seldom get the warning message:
> PRIMARY and INDEX keys should not both be set for column `ID`
>
> I understand its meaning, but I was wondering to what extent having a
> field indexed AND being a primary key might slow down/speed up my
> queries.
>
> Is that gonna take twice the time if I am searching on the ID field,
> just because there are two indexes?
>
> I'd like to have a rough idea of how serioulsy I need to avoid these.

Creating a PRIMARY KEY will automatically create an index.

Why would you create a second index for that field?

With regards,

Martijn Tonies
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Thread
Double indexes on one fieldYannick Warnier3 Oct
  • Re: Double indexes on one fieldMartijn Tonies3 Oct
    • Re: Double indexes on one fieldYannick Warnier3 Oct
      • Re: Double indexes on one fieldBastian Balthazar Bux3 Oct
        • Re: Double indexes on one fieldYannick Warnier3 Oct
  • Re: Double indexes on one fieldAlec.Cawley3 Oct