Query for list of attribute instead of tuples in SQLAlchemy

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When passing in ORM-instrumented descriptors such as a column, each result is a named tuple, even for just one column. You could use the column name in a list comprehension to ‘flatten’ the list (you can drop the .all() call, iteration retrieves the objects too):

result = [r.id for r in session.query(MyModel.id)]

or use the fact that it’s a tuple when looping a for loop and unpack it to a single-element tuple of targets:

result = session.query(MyModel.id)
for id, in result:
    # do something with the id

The latter could also be used in a list comprehension:

[id for id, in session.query(MyModel.id)]

You don’t really have any options to force the row results to be just the single id value.

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