[sql generation] fix missing join with outer joins w/ rhs invariant variable...
... where the principal where not the processed relation.
This led to major refactoring in outer join handling, which is now much
clearer and powerful.
Closes #1579228
# copyright %(year)s %(author)s, all rights reserved.
# contact %(author-web-site)s -- mailto:%(author-email)s
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%(long-license)s
"""%(distname)s precreate script, executed at instance creation time or when
the cube is added to an existing instance, before the schema is serialized.
This is typically to create groups referenced by the cube'schema.
"""