Re: Partitioning increasing query time

[Rick James]

This is a common misconception about PARTITION. Certain types of queries can benefit from PARTITIONing, others cannot, and may even get worse. Provide more details, and maybe we can help fix your case.
* SHOW CREATE TABLE tbl\G -- engine, indexes
* SHOW TABLE STATUS LIKE 'tbl'\G -- sizes
* EXPLAIN SELECT ...\G -- clues of inefficiencies
* EXPLAIN PARTITIONS SELECT ...\G -- which partition(s) it decided to use
* SHOW VARIABLES LIKE '%buffer%'; -- cache size
and surround them with [ code ] and [ / code ]