We are upgrading to mysql 5.7 and just discover that it is much slower than its 5.6 counter part. While both have almost identical config, the 5.6 version execute most of the sqls in milliseconds, ...

I have an app on heroku, running on Puma: workers 2 threads_count 3 pool 5 It looks like some requests get stuck in the middleware, and it makes the app very slow (VERY!). I have seen other peop...

I have an InnoDB table in MySQL 5.5.53 where simple updates like UPDATE mytable SET acol = 'value' WHERE id = 42; hang for several seconds. id is the primary key of the table. If I enable query...

How to handle it when some changes happen in specific table records ? public static function getAirportWithCache($iata_code){ $result = Airports::getDb()->cache(function ($db) use ($iata_code...

This is a pretty simple problem. Inserting data into the table normally works fine, except for a few times where the insert query takes a few seconds. (I am not trying to bulk insert data.) So I se...

I have news table and its related news_comment table. I have defined relation newsComment with news_comment table. If I execute this query: $result = News::getDb()->cache(function () use($id) ...

I have a large database application that uses mysqls query cache ability. I'd like to inspect the contents of the query cache to identify entries that should not get cached (e.g. by using SELECT SQ...

Is first level cache different from query cache in hibernate? I have seen articles mentioning about first level and query cache, so i am confused.

I have a slow database query that runs 18 seconds for the first run and 4 seconds as any subsequent run. I am trying to optimize it's "coldstart" execution time. But not able to reproduce it contin...

I'll try to be simple, so what i need is, perform a MySQL query (selecting records from a table) let's say ill produce the query with cron jobs or whatever every 5 minutes, and save this quer...

I once read in a performance blog that it is better to use PHP's date functions to set dates in a MySQL query instead of using mysql date functions like curdate() because mysql can then cache the q...

In a stats part of a Rails app, I have some custom SQL calls that are called with ActiveRecord::Base.execute() from the model code. They return various aggregates. Some of these (identical) querie...

Related to this question Premise: These are my assumptions, based on my reading, experience and understanding, they may be wrong, if they are, please comment and I'll edit the question. Query ...

In NHibernate Profiler I observed that when I use eager fetching on an association, using "left join fetch" in an HQL Query or .SetFetchMode() in a Criteria Query the query no longer gets cached in...

What if I have a query that gets called multiple times in a single thread, and I just want to cache that query (and its result) for that thread (or for that session since I'm using one session per ...