[PHP-DB] MySQL: Top $num results

2005-02-13 Thread ioannes 
If you use LIMIT row_count with ORDER BY, MySQL ends the sorting as soon as 
it has found the first row_count lines rather than sorting the whole table. 


http://dev.mysql.com/doc/mysql/en/limit-optimization.html
I need to get the top $num results from a completely sorted table (eg sorted 
on ID, ie the $num latest inserted rows).  Which functions should I be 
considering?

John 

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Re: [PHP-DB] MySQL: Top $num results

2005-02-13 Thread John Holmes 
ioannes wrote:
If you use LIMIT row_count with ORDER BY, MySQL ends the sorting as 
soon as it has found the first row_count lines rather than sorting the 
whole table. 

http://dev.mysql.com/doc/mysql/en/limit-optimization.html
I need to get the top $num results from a completely sorted table (eg 
sorted on ID, ie the $num latest inserted rows).  Which functions should 
I be considering?
LIMIT works that way, the write-up is just confusing. If you ORDER BY 
id DESC LIMIT 10, then you'll get the 10 highest values of id in the 
result. The write-up just means that MySQL isn't going to bother sorting 
the rest of the table after it finds the 10 highest (or whatever your 
limit is). Is that what you're after?

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