When we compile ech e query to a sequel, we have one important thing. Every query, no matter how complex it is, it's always compiled to just one sequel querry. And this is very important in the contest of relational data basis because when you have just one single querry, it's atomic. So you don't need like, an explicit transaction. You'lredulate e working. It's very important. We use lots of interesting tricks to make it happen.