how to learn to write a complex sql query??

Question

i know basics on sql but when it comes to retrieve data from multiple table on the basis of certain condition in where clause i failed to do them so i want to practice and make myself strong in that part specially in subquery so can anyone one assist me on how to write a complex sql query

Answer 1

It's hard (at least for me) to explain subqueries in an abstract way, although working with specific examples can be very useful IMHO. Please check this tutorial:
https://www.tutorialspoint.com/sql/sql-sub-queries.htm

Answer 2

I learned WITH clauses when I was struggling and that really helped me get good at sql