AdvancedAdvanced PostgreSQL
Theory: What is TOAST?
The query
SQL
-- Q: What is TOAST in PostgreSQL?
-- A: The Oversized-Attribute Storage Technique.
-- PostgreSQL uses a fixed page size (usually 8kB). If a row exceeds this
-- (like storing a massive JSON payload or long text), PostgreSQL automatically
-- compresses and splits the large data into multiple physical rows in a
-- hidden TOAST table, storing only a pointer in the main table.Note
“TOAST happens completely transparently to the user.