Stupid SQL Tricks

Joins This intends to provide a brief summary of JOIN operations. I’m attempting to follow standard SQL here where possible, thus avoiding, say, Oracle terminology like ANTIJOIN and SEMIJOIN. All SQL databases that I’ve encountered perform LEFT/RIGHT/INNER JOIN as expected, but others will show some variation. When in doubt, refer to your documentation. The generic […]

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Ubuntu Email Server with Postfix, Dovecot, and MySQL

————— Update November 2021: Added instructions for using Dovecot and Postfix with Let’s Encrypt. Also adjusted Postfix config to block auth attempts over port 25. This setup will get you 90%+ on mail server security tests. ————— ————— Update November 2020: If you’re on Ubuntu 20.04, these instructions still mostly work as written. There is […]

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