What SELECT FOR UPDATE, FOR SHARE, and a foreign key check actually write into the tuple header. t_xmax as a locker, the infomask bits that say so, MultiXactIds when two sessions lock the same row, an...

Thirty PostgreSQL schemas written by coding agents, loaded and measured. The indexes are competent; the cumulative cost is not.

PostgreSQL 19's new `WAIT FOR` command enables read-your-writes consistency on asynchronous replicas by letting individual reads wait for a specific WAL position.

WAIT FOR in PostgreSQL 19 lets a reader block until the replica has replayed a specific LSN. Measured against sticky routing, sleeps, and synchronous commit, on a replica that misses the write 99% of ...

AlloyDB offers Postgres wire compatibility with a divergent storage engine. A deep-dive review into HTAP claims, ScaNN limits, adaptive autovacuum, and costs

Nik and Michael are joined by Radim Marek to discuss MVCC, including his recent article on how Postgres chose to implement it compared to other systems.   Here are some links to things they mention...

The critics are right: PostgreSQL's MVCC bloats tables and amplifies writes. Oracle, InnoDB, SQL Server, MongoDB, LSM stores, and etcd answer the same four design questions differently, and each pays ...

Submit your talk for PGConf.PL 2026!

Watch a VACUUM cycle with pageinspect, pg_freespace, and pg_visibility: how a dead tuple loses its storage, then its index entry, then its slot, and how the freed space gets reused.

Same query, same rows, different SUM totals in PostgreSQL. The culprit is parallel aggregation over double precision floats, not a bug. Here is the mechanism and the fix.

A single NULL turns NOT IN into a query that silently returns zero rows, and the planner couldn't optimize around it for as long as anyone can remember, until a PostgreSQL 19 patch.

What pg_stat_statements records and what it quietly drops: the queryid jumble that splits one query into many rows, the frozen first-seen query text, and averages that hide your p99.

Views are PostgreSQL's cleanest abstraction and its most rigid one. How rewrite rules, attribute numbers, and the dependency catalog conspire to make every column change a teardown, and what is missin...

Interactive visualization of PostgreSQL's MVCC: xmin, xmax, snapshots, two concurrent sessions, and VACUUM reclaim.

The planner treats CTEs very differently depending on how you write them. Here's what happens under the hood, version by version, through PostgreSQL 18.

PostgreSQL 18 makes optimizer statistics portable. Export them from production and inject them into test databases to get realistic query plans without the data.

Slow PostgreSQL queries? Stale statistics are often to blame. Learn how the query planner uses statistics to estimate row counts and how to fix them.

Interactive visualization of PostgreSQL's 8KB page: header, line pointers, free space, and tuple data.

A byte-level tour of the 8KB page. PostgreSQL's atomic unit of storage. We deep dive into page headers, line pointers, and free space using pageinspect to see exactly how your data lives on disk.

Josef Machytka: Speaker portfolio

Learn how to interpret buffer statistics in PostgreSQL EXPLAIN output. Understand shared hits, disk reads, temp spills, and planning buffers to accurately diagnose and fix query performance bottleneck...

Extract seed data from any PostgreSQL database. Contribute to boringSQL/fixturize development by creating an account on GitHub.

How PostgreSQL actually manages memory, from shared_buffers and dirty pages to the OS page cache sitting underneath it all.

Nik and Michael are joined by Radim Marek from boringSQL to talk about RegreSQL, a regression testing tool for SQL queries they forked and improved recently. Here are some links to things they ment...