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Re: insert takes too long
Posted by: Rick James
Date: January 09, 2012 01:25AM

> some technical issues:
I need much more detail...

To assist in analyzing slow SELECTs, please provide
* SHOW CREATE TABLE tbl\G -- engine, indexes
* SHOW TABLE STATUS LIKE 'tbl'\G -- sizes
* EXPLAIN SELECT ...\G -- clues of inefficiencies
* SHOW VARIABLES LIKE '%buffer%'; -- cache size
and surround them with [ code ] and [ / code ]
How much RAM do you have?

Perhaps the cache is not a good size; perhaps something else
http://mysql.rjweb.org/doc.php/memory

Why do LEFT JOIN without testing for NULL?

Why have a subquery; wouldn't a JOIN work just as well (and possibly a lot faster)?

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