What are the nuances in big data?

Question

Database

Good morning everyone!
Such a question, for the purpose of training, I am going to develop a web parser - it will collect certain information from the Internet, I assume that the table will have about 20 columns with different parameters.
But the records, presumably, are about 500,000 - 1,000,000.
And, of course, the question arises - how to do all this correctly?
I’ll figure it out with the parser, I’m interested in exactly how to optimize data retrieval from the database? To make it work quickly and optimally even with a large number of requests, say, 20k - 50k per day (~10 hours a day)?
What can you immediately advise? What DB to use? What are the settings? DBMS? Books, articles?
By the way, I'm going to write in C++.
Experience in this area so far:
I just know how to create a database in MySQL, respectively SQL itself, i.e. I don’t know any subtleties of working with BIG DATA. While at the level of Select, Insert, etc.

Answer 1

500,000 - 1,000,000 is not BIG DATA. Any DB with any settings won't even notice.