Welcome back to the MySQL indexing series! We’ve already covered the nuances surrounding indexes in MySQL as well as walked you through B-tree indexes.
MySQL, however, has many other index types it can offer for your use case, and one of those indexes are hash indexes, too.
What are Hash Indexes?
In MySQL, hash indexes are indexes that are used in queries that use the equality operators like = or (which is the MySQL NULL safe equality operator, equivalent to the SQL Standard IS NOT DISTINCT FROM). Hash indexes are not used in other situations, so they can be