Hello,

I have a table, currently holding 128,978 rows...  In this table, I have a 
section column (int) and a price column (int).  Every row has a section of 1 
currently, every row has a price, ranging from 1 to 10,000.

I have an index on both columns separately.

Have a look at these two queries, can someone tell me why there is such a 
difference in speed of execution?  (Note difference in price qualifier)

########################################

SELECT *
FROM `table1`
WHERE price >0
AND section =1
ORDER BY price
LIMIT 0 , 30

Showing rows 0 - 29 (128,978 total, Query took 0.9462 sec)

Explain output: 1 SIMPLE table1 ALL section,price NULL NULL NULL 96734 Using 
where; Using filesort

########################################

SELECT *
FROM `table1`
WHERE price >1
AND section =1
ORDER BY price
LIMIT 0 , 30


Showing rows 0 - 29 (128,949 total, Query took 0.0008 sec)

Explain output: 1 SIMPLE table1 ALL section,price NULL NULL NULL 96734 Using 
where; Using filesort

########################################

Other info:

Query cacheing = off
MySQL version = 5.0.32
OS  = Debian Sarge

Sure, the second query returns 29 fewer records than the first, but should 
that make the difference in time?

Hope you can shed some light onto this :-)

Ta!

Chris. 



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