What do you do if your large-scale database is becoming difficult to manage and optimize?

If a large-scale database becomes difficult to manage, study needs and performance bottlenecks. Tune queries and index structures to optimize performance. Consider partitioning tables to distribute data efficiently. Scale resources vertically or horizontally as needed. Automate routine tasks to reduce manual effort. Refactor the database schema or application design if necessary. Proactively monitor system health and performance. Best practices include regular maintenance, documenting changes, and staying current with advancements in database technologies. These steps can help us effectively manage and optimize large-scale databases for optimal performance and scalability.

Assessing the situation by the error messages configured via email or nay third party tool which we are getting is the place to take notes. --Check the threshold set for the CPU in the server. --Long running queries which are running above the set threshold -- Active session count -- Schedule jobs run time

To optimise the query, first check their explain plan which gives the clear explanation of the query and the types of Indexes being used, the joins,nested loops, sub queries etc. Then with that we will get the cost and the data retrieval information (if data gets fetched from memory or disk) If any unused indexes are present, if the table goes for full table scan even when index is present, check the index status Check for stale statistics at the table level.

Use common sense But even before scaling try tuning the query based on the error it is throwing. With cloud computing we can scale resources just like that, but don't go for it blindly, first get the insights and before going for horizontal scaling, try to go for vertical scaling.

This varies from environment to environment, please be very careful before doing any automation, test in non prod and then implement in prod. Try automating the regular tuning tasks, suppose a job runs for 20mns, after that update the stats of the objects being used. If we feel objects get stale on a daily basis,work closely with the application team and get the objects involved in it. Pull the objects and try to run an update stats on them, then schedule the job based on the issue.

The first step is to act quickly. For this continuous monitoring is best, whether to schedule via crontab or any GUI. Set the metrics with priority level normal,high and act else it will lead to some serious trouble.