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database greenhorn (discuss.tchncs.de)

submitted 1 week ago* (last edited 1 week ago) by [email protected] to c/[email protected]

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hi my dears, I have an issue at work where we have to work with millions (150 mln~) of product data points. We are using SQL server because it was inhouse available for development. however using various tables growing beyond 10 mln the server becomes quite slow and waiting/buffer time becomes >7000ms/sec. which is tearing our complete setup of various microservices who read, write and delete from the tables continuously down. All the stackoverflow answers lead to - its complex. read a 2000 page book.

the thing is. my queries are not that complex. they simply go through the whole table to identify any duplicates which are not further processed then, because the processing takes time (which we thought would be the bottleneck). but the time savings to not process duplicates seems now probably less than that it takes to compare batches with the SQL table. the other culprit is that our server runs on a HDD which is with 150mb read and write per second probably on its edge.

the question is. is there a wizard move to bypass any of my restriction or is a change in the setup and algorithm inevitable?

edit: I know that my questions seems broad. but as I am new to database architecture I welcome any input and discussion since the topic itself is a lifetime know-how by itself. thanks for every feedbach.

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[–] [email protected] 2 points 6 days ago

If you are new to something and want to learn, seek resources and educate yourself with them. Learning takes time, and there are no shortcuts.

A hot DB should not run on HDDs. Slap some nvme storage into that server if you can. If you can't, consider getting a new server and migrating to it.

SQL server can generate execution plans for you. For your queries, generate those, and see if you're doing any operations that involve iterating the entire table. You should avoid scanning an entire table with a huge number of rows when possible, at least during requests.

If you want to do some kind of dupe protection, let the DB do it for you. Create an index and a table constraint on the relevant columns. If the data is too complex for that, find a way to do it, like generating and storing hashes, sorting lists/dicts, etc just so that the DB can do the work for you. The DB is better at enforcing constraints than you are (when it can do so).

For read-heavy workflows, consider whether caches or read replicas will benefit you.

And finally back to my first point: read. Learn. There are no shortcuts. You cannot get better at something if you don't take the time to educate yourself on it.