coding_chalenges.md

1. Can practice coding challenges with codility since this a platform used for coding challenges. Challenges in different programming languages, but unfortunately not in SQL.
2. A list of technical question here, which includes SQL, python and algorithms.
3. Interviewbit offers a long list of scenario SQL questions one can study from along with practice with a couple of multiple choice questions.
4. Pgexcercises is a good platform that provides a dataset and an extensive series of postgreSQL queries to practice with.
5. This article provides 42 SQL questions one can study from.
6. Initial questions about SQL at an interview:

• What functions do you know in SQL?
• How do you use SELECT in a query?
• How do you use JOINS in a query?
• How would you write in example query with SELECT and functions?