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Re: How to partition by City \ State
Posted by: Rick James
Date: December 20, 2012 10:00PM

1. (re: the error message) When alphabetizing a pair of things (think lastname, firstname), the first field changes the slowest.

2. Having a thousand partitions may hurt more than help. I generally recommend 20-50 PARTITIONs.

3. Let's see your SELECTs. Deciding on both partitioning and indexing is more complex than your simplistic question. Also, let's see the tentative CREATE TABLE.

4. See my tips in

5. Your use case may be "I need two clustered indexes", which is semi-possible. That means (perhaps):
PARTITION BY RANGE (city) & INDEX(state, city)
PARTITION BY RANGE (state) & INDEX(city, state)
I lean toward the former since the granularity of city is better. (In many statistics, such as population, CA makes up 10% of the US total. 10% is poor selectivity.)

Pending further info (#3, above), I suggest about 50 similar-sized partitions and
PARTITION BY RANGE (city) & INDEX(state, city)
plus perhaps other indexes.
`city`, if present in an index, should be last.
If you are using InnoDB, have a PRIMARY KEY, even if it is an artificial AUTO_INCREMENT.
Perhaps all secondary indexes should start with `state`.
Do not use utf8 for state; use CHAR(2) NOT NULL CHARSET ascii, pick either ascii_bin or ascii_general_ci, depending on whether you want case folding. (latin1 would do equally well)
`city` is less obvious. Some places (eg, San Jose, CA) have toyed with adding an accent. At which point, ascii is out; latin1 or utf8 would work about equally well.

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Written By
December 19, 2012 10:06PM
Re: How to partition by City \ State
December 20, 2012 10:00PM

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