VACUUM VACUUM — garbage-collect and optionally analyze a database Synopsis VACUUM [ ( option [, ...] ) ] [ table_and_columns …| PostgreSQL Documentation
ANALYZE ANALYZE — collect statistics about a database Synopsis ANALYZE [ ( option [, ...] ) ] [ table_and_columns [, …| PostgreSQL Documentation
49.2. Logical Decoding Concepts # 49.2.1. Logical Decoding 49.2.2. Replication Slots 49.2.3. Output Plugins 49.2.4. Exported Snapshots 49.2.1. Logical Decoding # Logical …| PostgreSQL Documentation
Before we discuss what VACUUM does and its implications, we need to understand how data is actually stored on disk. What happens when a tuple is inserted, updated, or deleted? Understanding this will help us understand what VACUUM does, why it’s needed, and its implications.| Dinesh Gowda
Write-Ahead Logs is a critical part of PostgreSQL, that ensures data durability. While there are multiple configuration parameters , there was no easy to monitor WAL activity, or what is generating it.| rjuju's home
Postgres uses an internal table called ‘pg_statistic’ to keep track of some metadata on all tables in the DB. Postgres’s Planner uses these statistics when estimating the cost of operations, which, if out of date, can cause the Planner to pick a suboptimal plan for our query. To trigger an update of ‘pg_statistic’ manually for a table, we can run ‘ANALYZE’ on it, helping the Planner estimate costs better and speeding up queries dramatically (in some cases).| Jaz’s Blog
As promised in a previous article, let’s discuss what MVCC is and why it is fundamenta to the workings of PostgreSQL. Even if you are a dev and not a DBA, I believe it is very helpful to have at least a rough understanding of how it works. Let us start with an example. We have a very simple schema such as: create table book ( book_id bigint, title varchar(256) ); insert into book (book_id, title) values (1, 'The lord of the rings'), (2, 'Crime and punishment'), (3, 'The moon is a harsh mist...| andreabergia.com