python - sqlAlchemy: Select from View -


there existing mysql database contains view lets columns 'vendor', 'product' , 'orderno'.

the view doesn't contain primary key. far know pk important orm. how possible model view in orm sqlalchemy?

if possible execute following query:

select exist(     select *     _viewname_     'vendor' = [value1] , 'product' = [value2] , 'orderno' = [value3] );

which should result in...

q = session.query(_viewname_).filter(         _viewname_.vendor == [value1],         _viewname_.product == [value2],         _viewname_.orderno == [value3]     ) session.query(q.exists()).scalar()

thanks help.


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