Re: why explain partition shows first partition in every select query?

[Rick James]

Common question, answered in some of these:

first partition - http://forums.mysql.com/read.php?106,518326 (I searched table on one partiton, but MySQL scanning two partitons)
*, partition, summary - http://forums.mysql.com/read.php?106,288561 (Partitioning with range(to_days) issue)
PARTITION - http://forums.mysql.com/read.php?10,586323 (count rows in a partition)
persistent innodb statistics - http://forums.mysql.com/read.php?106,566620 (timestamp, datetime as default value as current_timestamp [PARTITION])
REORGANIZE PARTITION - http://forums.mysql.com/read.php?10,549855 (help making event for auto delete of partitions)
DATETIME in PARTITION, DATETIME vs TIMESTAMP - http://forums.mysql.com/read.php?10,520797 (let table grow for two months then delete first month)
PARTITION - http://forums.mysql.com/read.php?24,507997 (MySQL performance help)
PARTITION NULL - http://forums.mysql.com/read.php?106,386051 (Partition Pruning)

Create a partition with few if any rows at the beginning.
Create a "future" partition so INSERTs after the last day won't fail.

For shifting partitions, see
http://mysql.rjweb.org/doc.php/partitionmaint