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PostgreSQL Pro | Database Mastery pinned «https://youtu.be/imBbqzIOQdo #ad»
5 Jul 2026, 05:05 UTC457 viewsread 7 August 2026 Advertisement
https://youtu.be/imBbqzIOQdo
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PostgreSQL Pro | Database Mastery pinned «Every RAG app, semantic search feature, and “related to this” button depends on one hidden operation: Find the nearest points among millions — fast. That sounds simple until you realize each document is stored as a high-dimensional vector, often with more…»
1 Jul 2026, 19:53 UTC554 viewsread 7 August 2026 Advertisement
Every RAG app, semantic search feature, and “related to this” button depends on one hidden operation:
Find the nearest points among millions — fast.
That sounds simple until you realize each document is stored as a high-dimensional vector, often with more than a thousand numbers. If your app has two million help articles, the brute-force approach means comparing the query against every single vector, every time.
T…
19 May 2026, 13:39 UTC885 views9 reactionsread 7 August 2026 Advertisement
Made an animated explainer on what actually happens when you go from no index to a B-tree index on a column. Hopefully useful for folks who are comfortable writing SQL but haven't dug into the execution side.
The core comparison the video covers:
Without index:
- Database scans every row sequentially
- Million-row table = up to 1 million comparisons
- Roughly 500ms on typical hardware
With B-tree index:
- Database…
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12 May 2026, 14:04 UTC857 views5 reactionsread 7 August 2026 Advertisement
"What happens when you type a URL into a browser?" is one of the most common technical interview questions. Most online answers cover DNS and TCP but skip everything that happens server-side — load balancers, reverse proxies, framework routing, database queries.
I made an animated explainer that walks through the full path: browser → DNS → TCP → TLS → load balancer → reverse proxy → application server → controller →…
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27 Mar 2026, 06:22 UTC≈1,240 views3 reactionsread 7 August 2026 📊 Week 10 done. Migrations without fear.
This week:
✅ Monday — Why ALTER TABLE is terrifying (and doesn't have to be)
✅ Tuesday — Safe vs dangerous operations (know before you run)
✅ Wednesday — 💰 Complete migration system (3⭐)
✅ Thursday — Three levels of rollback
The takeaway: every migration should have a written rollback plan before you run it. Takes 5 minutes. Saves you from the worst night of your career.
-…
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26 Mar 2026, 12:48 UTC942 views4 reactionsread 7 August 2026 🐌 Finding and fixing slow queries. The 80/20 approach.
Step 1: Find the worst offenders.
-- Enable if not already:
-- ALTER SYSTEM SET shared_preload_libraries = 'pg_stat_statements';
-- Restart PostgreSQL.
-- Top 5 by total time (these hurt your server the most)
SELECT
round(total_exec_time::numeric, 0) as total_ms,
calls,
round(mean_exec_time::numeric, 2) as avg_ms,
left(query, 100) as query
FROM…
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PostgreSQL Pro | Database Mastery pinned «🔐 Complete Monitoring Dashboard — See Everything, Pay Nothing What's inside: 📦 COMPLETE SYSTEM (3 ⭐) 1. HEALTH CHECK VIEW - Single query returns overall database health score (0-100) - Cache hit ratio, connection usage, bloat, replication lag …»
25 Mar 2026, 07:23 UTC692 views1 reactionsread 7 August 2026 Posted without readable text
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24 Mar 2026, 07:25 UTC632 views2 reactionsread 7 August 2026 📊 5 queries. Run them once a week. Know exactly what's happening.
QUERY 1: TABLE BLOAT AND SIZE
SELECT
relname as table_name,
pg_size_pretty(pg_total_relation_size(oid)) as total_size,
n_live_tup as live_rows,
n_dead_tup as dead_rows,
CASE WHEN n_live_tup > 0
THEN round(100.0 * n_dead_tup / n_live_tup, 1)
ELSE 0 END as dead_pct
FROM pg_stat_user_tables
ORDER BY pg_total_relation_…
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23 Mar 2026, 09:33 UTC522 viewsread 7 August 2026 🔍 Your database is talking to you. You're just not listening.
PostgreSQL collects stats on everything:
- Which queries are slow
- Which tables are bloated
- Which indexes are never used
- How much cache you're hitting
- Where connections are going
Most solo devs never look at any of it. Then wonder why things are slow.
Paid monitoring tools want $50-500/month to show you this data. But PostgreSQL already has it. Y…
Showing the 12 most recent of 20 posts we hold for @postgres. View and reaction counts are the latest single reading for each post, not a live figure, and a recent post is still accumulating both. A view count marked ≈ was rounded by Telegram before we ever saw it — t.me prints views in full below 1,000 and to three significant figures above, so ≈1,200,000 means somewhere between 1,150,000 and 1,249,999. Unmarked counts are exact. Text is reproduced from the public post preview and truncated for length.