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From:William R. Mussatto Date:March 6 2003 5:30pm
Subject:Re: Foreign keys and being FIRST index
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> http://www.mysql.com/doc/en/SEC457.html states that "there must be an
> index where the foreign key and the referenced key are listed as the
> FIRST columns." Will this restriction be lifted soon? It is incredibly
> frustrating. I don't see why they have to be indexes, and more
> importantly, I don't see why they have to be FIRST! Ugh.
>
Major performance hit would be a guess. Otherwise the database would have
to do a table scan. Think about how it would find the related record.  I
think is a requirement of db2 as well
>
>


William R. Mussatto, Senior Systems Engineer
Ph. 909-920-9154 ext. 27
FAX. 909-608-7061


Thread
Foreign keys and being FIRST indexDaevid Vincent6 Mar
  • Re: Foreign keys and being FIRST indexDan Nelson6 Mar
    • RE: Foreign keys and being FIRST indexDaevid Vincent6 Mar
      • Re: Foreign keys and being FIRST indexDan Nelson6 Mar
      • RE: Foreign keys and being FIRST indexKeith C. Ivey6 Mar
        • Multiple foreign keys?Daevid Vincent8 Mar
          • re: Multiple foreign keys?Egor Egorov8 Mar
  • Re: Foreign keys and being FIRST indexWilliam R. Mussatto6 Mar