Optimizing MySQL Queries et. Indexes

Things I have learned from troubleshooting mySQL queries Links Index och prestanda i MySQL Join types (from explain) MySQL Profiling Commands # Run query without cache SELECT SQL_NO_CACHE * from users where name like 'Ol%'; # Profiling SET SESSION profiling = 1; SHOW PROFILES; SHOW PROFILE FOR QUERY 3; SHOW STATUS LIKE 'Last_Query_Cost'; How to index/optimize Optimize OR Example: SELECT * FROM users where customerNumber='qwe' OR birthDate='2020-01-01'; You need an index for each OR, which will create a merge index on modern innoDB....

May 24, 2020  | 

Guitar pedals - What to buy

Pedals I wont buy Hungry Robot - Wardenclyffe Chase Bliss & Cooper - Generation Loss Pedals I might buy Behringer TO800 Vintage Tube Overdrive - 270 SEK Extra stuff 0.15m Patch Angled Jack - 25 SEK

March 18, 2020  | 

Remove subfolder from all git history

# Remove DIRECTORY_NAME from all commits, then remove the refs to the old commits # (repeat these two commands for as many directories that you want to remove) git filter-branch --index-filter 'git rm -rf --cached --ignore-unmatch DIRECTORY_NAME/' --prune-empty --tag-name-filter cat -- --all git for-each-ref --format="%(refname)" refs/original/ | xargs -n 1 git update-ref -d # Ensure all old refs are fully removed rm -Rf .git/logs .git/refs/original # Perform a garbage collection to remove commits with no refs git gc --prune=all --aggressive

February 27, 2020  |  🏷️Git

Dexed patches I like

Cartridge collections: Dexed_cart_1.0.zip Patches !Instruments > Misc > 2003.SYX > Brass&REV7: Punchy brass with slight echo !Instruments > Misc > DECKARD.SYX > SYNTHI 1-5: Versatile dark lead bass

February 19, 2020  |  🏷️Music

Heroes of Might and Magic VI does not start (black screen)

What I expected After installing Heroes of Might and Magic VI and then starting it through Steam, the game should enter the main menu. What I got The game screen is only black and never enters the main menu. How I solved it Go to My Documents > Heroes of Might and Magic VI. Open ProfileData with your favorite text editor Replace <gfx_Fullscreen2>Fullscreen</gfx_Fullscreen2> with <gfx_Fullscreen2>Windowed</gfx_Fullscreen2> Start game. Game will be in windowed mode, but it’s better than nothing

Kubernetes + GCloud + Kind Cheatsheet

Kubernetes + GCloud + Kind Cheatsheet Links Official Kubernetes Cheatsheet Kubectl Bash autocomplete source <(kubectl completion bash) Context - easy way of changing namespaces Contexts are saved to $HOME/.kube/config, so you can edit that file manually if you mess up. # One-time-only - create context kubectl config set-context iix --namespace=iix --user=kubernetes-admin --cluster=kubernetes # Later - use context kubectl config use-context iix Listing # List all images in the active namespace kubectl -n dev get pods -o jsonpath="{....

Using black or white text depending on background color

One problem which I encounter time and time again when creating a webpage or applications is matching text color with a changing background color. When creating a GUI you usually create a lot of white boxes with a black text on it, just to get sizes and stuff matching. Then later a designer or customer decides on a theme which affects how that box looks. Most of the time the background and text colors are hand-selected so they match well enough, but from time to time you have to create a box which can change background color on demand, and then you have to have the text color matching to make the box readable....

May 11, 2019  | 

Turn off caps-lock without the key

I usually don’t have a keyboard key mapped to caps, since I have my caps mapped to escape instead. However, from time to time it still gets activated. So to save me googling-time, this is the easiest way to turn it off: Alternative 1 xmodmap -e "clear Lock" Alternative 2 #! /usr/bin/env python from ctypes import * import subprocess class Display(Structure): """ opaque struct """ X11 = cdll.LoadLibrary("libX11.so.6") X11.XOpenDisplay.restype = POINTER(Display) display = X11....

HTTPS/SSL/TLS Verify installed certificate

Verify cert is correct openssl s_client -connect domoticz.iix.se:443 -servername domoticz.iix.se </dev/null Verify date of expiry for installed cert # HTTPS openssl s_client -connect example.com:443 -servername example.com 2>/dev/null </dev/null | openssl x509 -noout -dates # SMTP % openssl s_client -starttls smtp -connect smtp.iix.se:25 </dev/null 2>/dev/null | openssl x509 -noout -dates

Java Regex Cheatsheet

Escaping strings in regex replace s.replaceFirst(Pattern.quote("text to replace"), Matcher.quoteReplacement("replacement text"));

March 14, 2019  |  🏷️Regex