Interview Q&A / SQL & DBMS

INTERVIEW Q&A · 69 QUESTIONS

SQL & DBMS interview questions

Joins, keys, normalisation, indexes and transactions for placement and backend interviews.

  1. What is a FULL OUTER JOIN and how can you simulate it in MySQL?

    FULL OUTER JOIN returns all rows from both tables, matching where possible and filling NULLs where not. MySQL has no FULL JOIN, so combine a LEFT JOIN and a RIGHT JOIN with UNION.

    IntermediateQuick answer1 min read