PostgreSQLmedium

MVCC in Postgres: why don’t readers block writers?

Answer

Postgres uses MVCC (multi‑version concurrency control): updates create new row versions while readers use a snapshot to see a consistent view. That means readers can read old versions without blocking writers; VACUUM later cleans up dead tuples.

Related questions

PostgreSQL

How do `pg_stat_activity` and `pg_stat_statements` help in troubleshooting?

#postgres#monitoring#pg_stat_activity

PostgreSQL

Materialized view vs view: what’s the difference?

#postgres#views#materialized-view

PostgreSQL

LISTEN/NOTIFY: what problem does it solve?

#postgres#listen-notify#pubsub

PostgreSQL

Advisory locks: what are they and when would you use them?

#postgres#locks#advisory

PostgreSQL

BRIN index: when is it useful?

#postgres#brin#indexes

PostgreSQL

GIN vs GiST indexes: when would you use each?

#postgres#indexes#gin