On MacOS, use duti:
brew install duti
# vscode
duti -s com.microsoft.VSCode .md all
# confirm
duti -x md
# output: com.microsoft.VSCode
duti -s com.microsoft.VSCode .sql all
duti -s com.microsoft.VSCode .js all
duti -s com.microsoft.VSCode .ts allTo find what ID of the app you want to select, try:
osascript -e 'id of app "Visual Studio Code"'
# output: com.microsoft.VSCode