Re: [HACKERS] Outer joins

> > select * from t1 left|right|full outer join t2 on t1.x = t2.x;
> Will this be correct?
> SELECT * FROM t1, t2, t3, t4 LEFT OUTER JOIN ON t1.x = t2.x,
> t1.x = t3.x, t1.x = t4.x;

Left outer joins will take the left-side table and null-fill entries
which do not have a corresponding match on the right-side table. If
your example is trying to get an output row for at least every input
row from t1, then perhaps the query would be

select * from t1 left join t2 using (x)
left join t3 using (x)
left join t4 using (x);

But since I haven't implemented it yet I don't have much experience
with the outer join syntax...

- Thomas

--
Thomas Lockhart lockhart(at)alumni(dot)caltech(dot)edu
South Pasadena, California