Interview Q&A / PostgreSQL

INTERVIEW Q&A · 69 QUESTIONS

PostgreSQL interview questions

Indexes, EXPLAIN, transactions and isolation, JSONB and the Postgres specifics backend interviews probe.

  1. What is the difference between VACUUM and VACUUM FULL?

    VACUUM marks dead space reusable and runs alongside normal reads and writes, but usually does not shrink the file. VACUUM FULL rewrites the table into a new compact file, returning space to the OS, but takes an ACCESS EXCLUSIVE lock for the whole run.

    BeginnerQuick answer1 min read