Github user kaspersorensen commented on the pull request:
https://github.com/apache/metamodel/pull/20#issuecomment-96956463
But it is possible to do multiple joins using the existing API, it's just a
bit cumbersome IMO and it has no query parser support. Here is an example:
```
SELECT COUNT(*) FROM
(table1 INNER JOIN table2 ON table1.key1 = table2.key2) a
INNER JOIN table3 ON a.key2 = table3.key3
```
```
Table table1 = ...
Table table2 = ...
Table table3 = ...
FromItem joinPart1 = new FromItem(table1);
FromItem joinPart2 = new FromItem(table2);
FromItem joinPart3 = new FromItem(table3);
SelectItem key1 = new SelectItem(table1.getColumnByName("key"))
SelectItem key2 = new SelectItem(table1.getColumnByName("key"))
SelectItem key3 = new SelectItem(table1.getColumnByName("key"))
FromItem join1 = new FromItem(JoinType.INNER, joinPart1, joinPart2, new
SelectItem[] {key1}, new SelectItem[] {key2});
join1.setAlias("a");
SelectItem key2inJoin1 = new SelectItem(key2, join1);
FromItem join2 = new FromItem(JoinType.INNER, join1, joinPart3, new
SelectItem[] {key2inJoin1}, new SelectItem[] {key3});
Query q = new Query();
q.selectCount();
q.from(join2);
```
Very cumbersome in deed ... We very much need parsing here AND probably
also some more convenience constructors.
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