One way is to change:
files.Key
into:
{sql_nullable (SQL files.Key)}
That's a kind of cast into a nullable type, to match the type of the
other operand.
I don't see a way around changing types to indicate that any column of
an outer-joined table could be null.
On 07/03/2017 02:58 PM, Athene Noctua wrote:
I'm having trouble with a query using multiple joins, one of which is
an outer join:
SELECT * FROM posts
LEFT OUTER JOIN post_files ON post_files.Post = posts.Key
JOIN files ON post_files.File = files.Key
I think the type system assumes that posts_files.File will exist even
though a post might not have any associated files, and end ups with this:
Can't resolve type class instance
Class constraint:
{Post_files :
{File : nullify string string,
Post : nullify int (option int)}}
Reduced to unresolvable:
{File : nullify string string,
Post : nullify int (option int)}
Is this query resolvable in some way?
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