One of the things I struggle with as a newcomer to Python from Java, is if
I import a class from a namespace, I expect to find the code in that
namespace.
But I find namespace A includes namespace B, so you are forever chasing
around in IDE's to get your head around the structures..
Case in point:
sel = select([Jobmst.jobmst_id, Jobmst.jobmst_name, Jobmst.jobmst_prntid,
Jobmst.jobmst_type])
j2 = aliased(sel, name='j2')
j3 = aliased(Jobmst, name='j3')
print ('j2 type: ', type(j2))
print ('j3 type: ', type(j3))
j2 type: <class 'sqlalchemy.sql.selectable.Alias'>
j3 type: <class 'sqlalchemy.orm.util.AliasedClass'>
I had a
from sqlalchemy.sql import select
When I look in that I see Selectable comes from
.expression.Selectable
I use the docs and find this
<http://docs.sqlalchemy.org/en/latest/core/selectable.html?highlight=expression%20selectable#sqlalchemy.sql.expression.Selectable>
Says. Bases: sqlAlchemy.sqlexpression.ClauseElement
http://docs.sqlalchemy.org/en/latest/orm/query.html?highlight=aliasedclass#sqlalchemy.orm.util.AliasedClass
Says AliasedClass is ORM equivalent of sqlalchemy.sql.expression.alias()
... maintains a reference to 'real' Alias object
usage via orm.aliased(). orm.with_polymorphic()
Alias -> sql.sqlexpression.Alias
bases sqlalchmy.sql.expression.FromClause
http://docs.sqlalchemy.org/en/latest/core/selectable.html#sqlalchemy.sql.expression.Alias
My this point i'm totally confused. I wanted to ensure j2 or j3 were
interchangeable.
But without a big picture diagram I'm totally confused!
Is there such a diagram somewhere with the current 1.2 release please?
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