Undefer Hybrid Attributes

[Kent]

I notice that Hybrid Attributes don't show up as mapper properties (since they are class wide instead of mapper specific, I suppose).  I couldn't find documentation on whether I can "undefer" these?  Or can I create a synonym or column_property from a hybrid attribute in the mapper?

[Kent]

I suppose what I'm really after is a column_property (for class level) and plain descriptor (for instance level), which is exactly what Hybrid attributes are meant to be, but I wanted them to be part of the mapper and undeferred in some cases.

[Michael Bayer]

The hybrid attribute is a Python function that invokes when it's called.  So it doesn't make sense for it to be a column property since there is no attribute to be populated.  "Undeferred" also doesn't make any sense because the hybrid already calls a local in-Python function when accessed at the instance level, not a database call.

A traditional column_property() can be deferred or undeterred, and when called at the instance level will emit SQL to the database.

If you have an attribute that should only populate via SQL, then you need to just use a column_property().

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[Kent Bower]

That makes sense,
Thanks,

Kent

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