Backend Developer
SQL questions
19 questions on SQL for backend developers, easiest first.
Easy 10
- Stopping SQL injectioneasy
- Purpose of a database indexeasy
- Rows returned by a LEFT JOINeasy
- What a foreign key enforceseasy
- Atomicity in a money transfereasy
- COUNT and AVG with NULLseasy
- Filtering grouped resultseasy
- Duplicate emails despite a checkeasy
- What EXPLAIN tells youeasy
- Database user for the appeasy