How to optimize a query
I have the following query that might be taking a long time.
Optimize large running join query in mysql
Hi everyone,
I am trying to retrieve data using below query which is running forever. basically I am doing student level grouping by passing parameters from t4 tables rows.
SQL query related to performance, query table with less info vs. query table with more info?
Practising my SQL by creating an SQL for a grocery store.
MySQL functional index with IS NULL
I have a large table in MySQL with a slow query partly due to a condition like WHERE sent_at IS NULL. sent_at is a nullable datetime column but here we only want to check if it’s null so a standard index across all values would be wasteful.
Optimize query with agregate function
I have this query, which durate 1.3s. Why is so long when I have all indexes? Can I somewhat optimize or simplify this query? I need to calculate data online. Saving to a table and regenerating once in a while is not something I want.
When MRR used in mysql Queries
We are using MySQL 8.0.35, Here we are facing some slow queries in our production, When we checked the explain plan In all slow queries there is an hint “Using MRR”.