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Re: Dimensional model, user ids and number of tables
Posted by: Rick James ()
Date: June 25, 2009 09:15PM

20K tables is pushing things. I recommend against that approach.

50M rows, even with a compound primary key, is big, but not impossible. Remember, indexes are in BTree format, which grows only as the log of the number of rows.

Let's get into what the 10K-100K rows are for each user. Having to fetch that many rows will take a noticeable amount of time, regardless of the structure. And, if you have to join that many rows between two tables, it will be seriously slow.

PARTITIONing is unlikely to help any. Sharding could, but that involved more hardware.

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Subject Views Written By Posted
Dimensional model, user ids and number of tables 8069 Mads Jensen 06/24/2009 01:07PM
Re: Dimensional model, user ids and number of tables 3898 Rick James 06/25/2009 09:15PM
Re: Dimensional model, user ids and number of tables 3696 Mads Jensen 06/26/2009 07:17AM
Re: Dimensional model, user ids and number of tables 3742 Rick James 06/27/2009 12:24AM
Re: Dimensional model, user ids and number of tables 3676 Mads Jensen 06/30/2009 12:48PM
Re: Dimensional model, user ids and number of tables 3703 Rick James 06/30/2009 10:00PM
Re: Dimensional model, user ids and number of tables 4319 Mads Jensen 07/03/2009 04:20AM
Re: Dimensional model, user ids and number of tables 3578 Rick James 07/03/2009 02:21PM
Re: Dimensional model, user ids and number of tables 3591 Mads Jensen 07/04/2009 03:20AM


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