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Re: is read block write?
Posted by: Rick James ()
Date: October 20, 2011 10:54PM

Data_length: 5959082744
Data_free: 1419788748
Recommend:
OPTIMIZE TABLE trade;
Caution: It may take more than an hour to run; all references to the table will be blocked during the OPTIMIZE.

> Rows_sent: 45 Rows_examined: 120460
However, there is no good reason for it to examine more than 45. Perhaps this will make it faster:

select  id, product, cas_no, company, post_date,
        pubDate, mtype_en, poster, cate1
    from  sell s
    JOIN  
      ( SELECT  id
            FROM  sell
            order by  pubDate desc
            limit  0,45
       ) x ON x.id = s.id
    where  1
      and  pubDate >= date_add(current_date(), interval -14 day)
    order by  pubDate desc, mtype_en desc, post_date desc;
Caveats:
* If you change the WHERE clause, this may not work as well.
* The exact ordering _may_ be different.

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Subject Views Written By Posted
is read block write? 2165 h ch 10/10/2011 01:02AM
Re: is read block write? 1098 Rick James 10/12/2011 06:05AM
Re: is read block write? 711 h ch 10/18/2011 11:50PM
Re: is read block write? 863 Rick James 10/20/2011 10:54PM


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