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From:Reindl Harald Date:September 27 2012 9:25pm
Subject:Re: checking progress of alter table on a MyISAM table
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Am 27.09.2012 23:15, schrieb Larry Martell:
>> Indexes are slowing this down. your calculation of 79 hours should be
>> correct, only if there are no unique indexes, otherwise this will slow down
>> more as the data increases.
> 
> It is what it is - there's no free lunch - dropping the indexes, doing
> the alter, and re-adding the indexes would probably take just as long

you refuse to understand the implication of indexes
it would NOT take so long - this was proven thousands
of times by many people all over the world

having a unique index on a table with many rows means
a lot of overhead for EVERY single insert/update

without the key you avoid the complete overhead
and do it once at the end - why do you not simplay
make any test table and compare insert 50.000 rows
with and without keys on the test-table

this takes a few minues and after that you understand
how large the overhead is and that it is grwoing with
the table


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Thread
checking progress of alter table on an InnoDB table (Was: Re:checking progress of alter table on a MyISAM table)Larry Martell27 Sep
  • RE: checking progress of alter table on an InnoDB table (Was: Re:checking progress of alter table on a MyISAM table)Rick James27 Sep
    • Re: checking progress of alter table on an InnoDB table (Was: Re:checking progress of alter table on a MyISAM table)Larry Martell27 Sep
    • Re: checking progress of alter table on an InnoDB table (Was: Re:checking progress of alter table on a MyISAM table)Akshay Suryavanshi27 Sep
      • Re: checking progress of alter table on an InnoDB table (Was: Re:checking progress of alter table on a MyISAM table)Larry Martell27 Sep
        • Re: checking progress of alter table on an InnoDB table (Was: Re:checking progress of alter table on a MyISAM table)Akshay Suryavanshi27 Sep
          • Re: checking progress of alter table on an InnoDB table (Was: Re:checking progress of alter table on a MyISAM table)Larry Martell27 Sep
            • Re: checking progress of alter table on a MyISAM tableReindl Harald27 Sep
          • Re: checking progress of alter table on an InnoDB table (Was: Re:checking progress of alter table on a MyISAM table)Larry Martell28 Sep