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 MVCC in databases?

    MVCC keeps multiple versions of a row so readers see a consistent snapshot while writers create new versions. This lets reads and writes proceed without blocking each other. PostgreSQL, MySQL InnoDB and Oracle use it.

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