python - Sqlalchemy two filters vs one and -


this straight forward question. better use, 2 filters or 1 and_? there difference? 

session.query(test).filter(test.id == x).filter(test.test == y).all()

vs

session.query(test).filter(and_(test.id == x, test.test == y)).all()

they give me same result there difference speed or else?

both queries in question have same performance. can test inspecting resulting sql query.

from sqlalchemy import column, integer, string, and_ sqlalchemy.ext.declarative import declarative_base sqlalchemy.orm.query import query  base = declarative_base()  class test(base):     __tablename__ = 'test'     id = column(integer, primary_key=true)     test = column(string(50))   print(query([test]).filter(test.id == 1).filter(test.test == 'foo'))  # select test.id test_id, test.test test_test # test # test.id = :id_1 , test.test = :test_1  print(query([test]).filter(and_(test.id == 1, test.test == 'foo')))  # select test.id test_id, test.test test_test # test # test.id = :id_1 , test.test = :test_1

both queries produce same sql expression.

and_ commonly used when you're using sql expression query directly against tables, or when nesting multiple predicates within or_.


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