You are correct. There are many cases heard by judges everyday. If comparing to the number of cases to the number of judges, it is overload for the judges.
That is why there are many cases presided over by the judges in the same court room everyday. But it is on a one-by-one case basis.
If a case is complicated, the judge will allow to have the continuous hearing without interruption by other cases.
Just for your information, we call the court room in Thailand a throne, because the judge is working under the sovereignty of the King.