Want to find the value at the nth percentile with #SQL? Use PERCENTILE_CONT ( n ) WITHIN GROUP( ORDER BY close_price ) n is between 0 and 1, so 0.5 => median 0.75 => 75th percentile 0.99 => 99th percentile @vladmihalcea.bsky.social demos

How does MVCC (Multi-Version Concurrency Control) work vladmihalcea.com/how-does-mvc...

💻 I'm now working on the demo and slides for my DevTalks presentation. ⚡ If you have never worked with Blaze Persistence from the amazing Christian Beikov, then prepare yourself to be amazed!

How does the 2PL (Two-Phase Locking) algorithm work vladmihalcea.com/2pl-two-phas...

A beginner’s guide to ACID and database transactions vladmihalcea.com/a-beginners-...

🐘 With thousands of extensions available, PostgreSQL is like the WordPress of the database world. gist.github.com/joelonsql/e5...

The maximum number of database connections vladmihalcea.com/maximum-data...

A beginner’s guide to database deadlock vladmihalcea.com/database-dea...

Optimistic vs. Pessimistic Locking vladmihalcea.com/optimistic-v...

The race condition that led to Flexcoin bankruptcy vladmihalcea.com/race-conditi...

As a software engineer, it's very important to learn about Gall’s Law, which states that complex systems cannot be created successfully from scratch. In reality, even large systems, such as Netflix, Google, or Facebook, have started small and built incrementally over the course of decades.

How to index JSON columns using MySQL vladmihalcea.com/index-json-c...

A beginner’s guide to SQL injection and how you should prevent it vladmihalcea.com/a-beginners-...

How to get a JSON property value using PostgreSQL vladmihalcea.com/json-propert...

How to map a JSON object to a relational database table using MySQL JSON_TABLE vladmihalcea.com/mysql-json-t...

How to fetch multiple to-many relationships with jOOQ MULTISET vladmihalcea.com/fetch-multip...

SQL Seek Method or Keyset Pagination vladmihalcea.com/sql-seek-key...

MySQL rewriteBatchedStatements configuration property vladmihalcea.com/mysql-rewrit...

How to limit the SQL query result set to Top-N rows only vladmihalcea.com/sql-query-li...

PostgreSQL reWriteBatchedInserts configuration property vladmihalcea.com/postgresql-m...

Pagination best practices vladmihalcea.com/pagination-b...

AI is a great candidate for TED talks because: - It started as an underdog, with everyone dismissing and making fun of it prior to 2023 - It has studied hard and keeps on learning new things daily - It became successful and now has billions of customers I see a great motivational speech here!

Why you should set sendStringParametersAsUnicode to false with SQL Server vladmihalcea.com/sql-server-j...

Answer: Non-Repeatable Read vs Phantom Read stackoverflow.com/a/51123574/1...

SQL Server useBulkCopyForBatchInsert configuration property vladmihalcea.com/sql-server-u...

How does a Clustered Index work vladmihalcea.com/clustered-in...

Software development is non-deterministic, whether with humans or AI. Integration tests are the ones that make your application deterministic.

PostgreSQL Heap-Only-Tuple or HOT Update Optimization vladmihalcea.com/postgresql-h...

A beginner's guide to PostgreSQL Index Types vladmihalcea.com/postgresql-i...

While running Hupersistence, I always wondered why clients were thanking me for answering their emails so fast, and after a short stint in the corporate world, I finally understood what they meant. 😀

How do UPSERT and MERGE work in Oracle, SQL Server, PostgreSQL and MySQL vladmihalcea.com/how-do-upser...

A beginner's guide to database Index Selectivity vladmihalcea.com/index-select...

Optimistic vs. Pessimistic Locking vladmihalcea.com/optimistic-v...

Why you should definitely learn SQL Window Functions vladmihalcea.com/why-you-shou...

Default Database Primary, Foreign, and Unique Key Indexing vladmihalcea.com/default-data...

I post all sorts of stuff on social media. Technical posts, like deep-dive articles, barely get 2000-3000 impressions. Silly posts like this one can easily go to 70k-100k impressions.

A Beginner's Guide to SQL Recursive WITH CTE queries vladmihalcea.com/sql-recursiv...

A Beginner's Guide to PostgreSQL Auto Explain vladmihalcea.com/postgresql-a...

If you're using PostgreSQL and want to learn how to get the best out of it, then you should definitely read Just Use PostgreSQL! by Denis Magda. I'm now reading it and learning a lot of stuff! www.manning.com/books/just-u...

A Beginner's Guide to SQL CTE – Common Table Expression vladmihalcea.com/sql-cte-comm...

SQL Derived Table or Inline View vladmihalcea.com/sql-derived-...

A Beginner's Guide to the SQL EXISTS and NOT EXISTS vladmihalcea.com/sql-exists/

📢 On the 25th of September, I'm going to give a talk at #DevTalks in Cluj-Napoca. 🍃 If you're using Spring Data JPA and want to learn how to get the best out of it, then you're going to love this presentation. www.devtalks.ro/cluj#agenda

Merge Join Algorithm vladmihalcea.com/merge-join-a...

Hash Join Algorithm vladmihalcea.com/hash-join-al...

Nested Loop Join Algorithm vladmihalcea.com/nested-loop-...

A Beginner’s Guide to SQL LEFT JOIN vladmihalcea.com/sql-left-join/

A Beginner’s Guide to SQL CROSS APPLY vladmihalcea.com/sql-cross-ap...

A Beginner’s Guide to SQL INNER JOIN vladmihalcea.com/sql-inner-jo...

The best way to use one-to-one table relationships vladmihalcea.com/one-to-one-t...