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 NATURAL JOIN and why do many developers avoid it?

    NATURAL JOIN automatically joins on all columns with the same name in both tables. It is risky because adding or renaming a column silently changes the join. Explicit ON or USING is safer.

    IntermediateQuick answer1 min read