Check if DB is up snippet

snippet_db_connect_loop_basic.sh

# vars
NOT_CONNECTED=1
COUNT=0
#...
# run server, etc.
#...
echo "Attempting to connect to SQL SERVER...";
while [ "$NOT_CONNECTED" != "0" ]; do
  # Specifically for the MSSQL docker container. Run and try to do a query. Dump all output to /dev/null
  /opt/mssql-tools/bin/sqlcmd -e -S "$DB_ADDR" -U "$DB_USER" -P "$SA_PASSWORD" -b -Q "SELECT * FROM sys.databases;" 2>&1 > /dev/null
  NOT_CONNECTED=$? # Check if the last command failed or not
  COUNT=$[$COUNT + 1]; # Increase attempt counts
  
  # Only print if we're still not connected
  if [ "$NOT_CONNECTED" != "0" ]; then
    echo "Not connected ($COUNT attempt(s))";
    if (( $COUNT > 60 )); then
      echo "TIMEOUT (approx 60s) EXCEEDED. Could not connect to DB. Goodbye.";
      exit 1;
    fi
    sleep 1;
  fi # not connected IF
done

# Now you're connected!