Mysql partitioning
From wikinotes
Partitioning is a write-optimization.
A partitioned table's contents are stored in different locations (ex. different servers).
A partitioning key is passed to a function to determine which partition a row or column should belong to.
Partitions must share the same storage-engine
Frequently a globally relevant identifier is used as the partitioning key (ex. a user).
then all of the rest of their data (ex. comments, projects, posts, ..) are stored on the same database instance.
Partition Methods
horizontal: rows are partitioned vertical: cols are partitioned
Partitioning Strategies
Partition Introspection
EXPLAIN PARTITIONS SELECT * FROM users; # list partitions, partition-key for query