I would like to have a query condition based on a property of a node
selected by a left outer join. If the left joined node exists, I have no
problem. If the left joined node does not exist, I cannot use the
property in a constraint.
I tried doing something like this:
SELECT *
FROM [m:foo] AS foo
LEFT OUTER JOIN [m:foochild] AS maybe ON ISSAMENODE(maybe,foo,'fc1')
WHERE maybe.bar <> 'X'
I understand that this is like SQL and the where clause will evaluate to
false if maybe.bar is null. So I tried this:
SELECT *
FROM [m:foo] AS foo
LEFT OUTER JOIN [m:foochild] AS maybe ON ISSAMENODE(maybe,foo,'foo')
WHERE maybe.bar IS NULL OR maybe.bar <> 'X'
But that also returns null if maybe is null. So I tried:
SELECT *
FROM [m:foo] AS foo
LEFT OUTER JOIN [m:foochild] AS maybe ON ISSAMENODE(maybe,foo,'foo')
WHERE NOT maybe.bar IS NOT NULL OR maybe.bar <> 'X'
But that does not work either.
Is there a way to get something to evaluate to true if a left outer
joined node is null?
--
Stephen Byrne
[email protected]
