With a quick google search I found this stackexchange answer to preload data into cache with the pg_prewarm extension (from Postgres 9.4) http://dba.stackexcha

With a quick google search I found this stackexchange answer to preload data into cache with the pg_prewarm extension (from Postgres 9.4) http://dba.stackexchange.com/a/116536 http://dba.stackexchange.com/a/116536 But this doesn't guarantees that the data will stay in the cache because: "Prewarmed data also enjoys no special protection from cache evictions, so it is possible for other system activity may evict the newly prewarmed blocks..." In MySQL you can create tables with the MEMORY storage engine: https://dev.mysql.com/doc/refman/5.5/en/memory-storage-engine.html https://dev.mysql.com/doc/refman/5.5/en/memory-storage-engin...