How to Resolve "Deadlock Found When Trying to Get Lock" in MySQL
Two transactions each hold a lock the other one needs, and MySQL detects the standoff and kills one of them rather than letting both wait forever. A deadlock...
Blog
All troubleshooting articles, newest first.
How to Fix "Table Is Marked as Crashed and Should Be Repaired" in MySQL
A query against a table that was working fine suddenly fails, and MySQL reports the table itself is corrupted. This error is specific to the older MyISAM...
How to Resolve "MySQL Slow Query Log Not Recording Queries"
You've enabled MySQL's slow query log expecting to catch problematic queries, but the log file stays empty even though you know slow queries are happening....
How to Fix "Error 1054 (42S22): Unknown Column in Field List"
A query fails claiming a column doesn't exist, even though you're confident it's really there. This error means MySQL parsed your query successfully but...
How to Fix "bash: command not found" After Updating PATH Variable
You add a new directory to your PATH, expecting a command to work afterward, but the shell still can't find it. This almost always means the change either...
How to Resolve "sudo: unable to resolve host" Error in Ubuntu
Every sudo command prints a hostname resolution warning before actually running, even though your network connection works fine otherwise. This is sudo trying...
How to Fix "chmod: cannot access: No such file or directory" in Bash Script
Your script calls chmod on a file that should exist, but it fails claiming the file isn't there. This is a path resolution problem — the file exists somewhere,...
How to Resolve "bash: ./script.sh: /bin/bash^M: bad interpreter"
You try to run a shell script and bash refuses, blaming a broken interpreter path with a strange ^M character in it. The script's shebang line looks completely...
How to Fix "Crontab Script Not Running Automatically" in Linux
Your script runs perfectly when you execute it manually, but cron never seems to trigger it at the scheduled time. Cron jobs run in a stripped-down environment...