I'm saving about 3GB per day of financial orderbook data to a database (currently Mysql). In the coming weeks, I'm going to save trade and quote (bids/asks) data too.
Data is structured, but I'm doing many searches on it, for example get all orderbooks by stock symbol (which is very slow somehow). Or get all bids/asks by symbol. Currently, a query might take 5 seconds or so (select X where ticker like Y), and the size is only 20GB. In the future, at 1TB, I'm a bit concerned regarding speed per query.
What are some recommendations for cost efficient but also performant solutions for this task? I'm currently running a Mysql database on Digitalocean. Appreciate any help, also any tips regarding what to look into (indexing, sql vs nosql, performance tips, which specific databases would be better suited).