Postgresql medium
What is the purpose of the 'TOAST' (The Oversized-Attribute Storage Technique) subsystem in the PostgreSQL storage engine?
- A It provides a mechanism for automatic database-level compression of all integer columns.
- B It handles the storage of large field values that exceed the standard 8KB page size limit.
- C It manages the transition of old table data to colder storage tiers on secondary SSD disks.
- D It provides a secure vault for storing encrypted connection strings and API master keys.
Answer: B. It handles the storage of large field values that exceed the standard 8KB page size limit.
TOAST moves large attributes (like long text or large blobs) into a secondary table, keeping the main table rows small. This ensures that sequential scans of the main table remain fast even if some rows contain huge payloads.
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