calling all sql experts. I have the following select statement: 

```
SELECT 1
  FROM table1 t1
  JOIN table2 t2 ON t1.id = t2.id
 WHERE t1.field = xyz

```

I'm a little bit worried about the performance here. Is the where clause evaluated before or after the join? If its evaluated after, is there way to first evaluate the where clause? 

The whole table could easily contain more than a million entries but after the where clause it may be only 1-10 entries left so in my opinion it really is a big performance difference depending on when the where clause is evaluated.

Thanks in advance.

Dimi