Introduction
The very basics
Infinite looping
Processing trees with recursive CTEs
Processing graphs with recursive ctes
28. Travelling salesman 1
Summary

## Instruction

Okay! Quite an impressive query, wasn't it? Let's build it, step by step, from scratch now.

## Exercise

We start in London, so let's show the information for London first. We need the following columns:

• Path – for now, it's simply the city name,
• Lat,
• Lon,
• TotalDistance – the total distance travelled between cities – for now it's equal to 0.0,
• CountPlaces – the number of cities visited; it's equal to 1 at this point.

All the information can be found in the City table.