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From:Paul DuBois Date:February 26 2002 3:30pm
Subject:Re: Is it searching Time in MySql is Linear ????
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At 20:48 +0530 2/26/02, Battini, Chandrashekar wrote:
>	Hi ,
>	   I am using Mysql in Linux OS. I created a table in Mysql. The
>table has 3 fields and one is Primary key among them. I have populated 40K
>entries in the table. While populating the entries in the table,  For each
>500 entries that i populated in the table, i have searched for a single
>entry in the table using primary key and measured the time taken to complete
>the search.    As the Number of entries grows in the table, the time taken
>to search for a entry  are  increasing linearly. Why is the time increases
>linearly?

It's impossible to say, because you don't show your table structure or
your queries.  Typically, an index should speed up lookups, but it's possible
you're writing them in such a way that the index isn't being used.

>  Is this the Mysql behavior? I read in Mysql manual that, by
>default Mysql creates index file(.MYI) on Primary Key using B-Tree
>algorithm.
>
>
>	  My Question is , When Mysql using B-Tree for searching, Why the
>time taken to search for entries increases linearly as the entries in the
>table grows? According to B-Tree algorithm, the time has to be O(log n) ,
>which is not linear as n increases. Even though if we  assume disk overhead
>as some constant (typically O(log m), where m is the order  ), it is not
>linear.  Why is this happening ? Can any one help me out?
>
>
>	Thank You,
>	Battini Chandra Sekhar.

Thread
Is it searching Time in MySql is Linear ????Chandrashekar Battini26 Feb
  • Re: Is it searching Time in MySql is Linear ????Paul DuBois26 Feb