In wich order are joins made:

SELECT * FROM table1 t1 LEFT JOIN t2 ON (t1.key1=t2.key2) LEFT JOIN t3
ON (t1.key2=t3.key1)

t1 and t2 are joined first, and then t3 are joined by the result of
t1+t2, right?

SELECT * FROM table1 t1 INNER JOIN t2 ON (t1.key1=t2.key2) LEFT JOIN t3
ON (t1.key2=t3.key1)

Same order as the first statement, right?

Next question. Will there be support for the USING keyword in joins?