Question

I’m trying to construct a SQL query that I think requires multiple JOIN’s, but I don’t know the syntax.

Here is a rough example of the Tables (with column names) for each.

T1 (key, name)

T2 (key, fkeyT1)

T3 (key, fkeyT2)

I want to get all the rows from T3 that are linked to rows in T2 that are linked to rows in T1 with a given name.

I figure I’ll need at least 2 JOIN’s; I’ve got the first JOIN I think:

SELECT *
FROM T3 INNER JOIN T2
ON T3.fkeyT2 = T2.key

I figure I’ll need to take these results and do another JOIN with T1 but I’m not sure of the syntax.

Answer 1

You probably want something like

SELECT *
  FROM t3 INNER JOIN t2 ON (t3.fkeyT2 = t2.key)
          INNER JOIN t1 ON (t2.fkeyT1 = t1.key)
 WHERE t1.name = 'Foo'