PostgreSQL uses MVCC (Multi-Version Concurrency Control) to execute transactions and queries in parallel over a consistent view/snapshot of data. Each user record may exist in multiple versions simultaneously, with each version visible to a particular set of transactions.
You'll learn how MVCC functions internally by running various hands-on experiments.
0:00 Introduction to PostgreSQL MVCC
0:55 Exploring hidden columns
4:09 Generating multiple versions for the same row
6:45 Looking into PostgreSQL pages with pageinspect
9:12 Creating a custom function for advanced analysis
12:59 Garbage collecting all versions with vacuum
Step-by-step instructions. Repeat on your end:
github.com/dmagda/DevMastersD...
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