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.
