使用SqlAlchemy关联属性过滤association_proxy

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我有一个使用SA的 association_proxy 建模 的多对多
（开发人员和项目）关系。集合（每个项目的开发人员和每个开发人员的项目）工作正常，但我需要过滤关联本身的属性（状态）。像这样的东西（不起作用）： __
activeDevelopers = s.query(Developer).filter_by(Developer.developerProjects.status == 'active').all()
我想念什么？这是完整的测试代码：
% R& p3 j9 ^9 V# J( S( i! q' p$ _import logging
from sqlalchemy import create_engine, Table, Column, Integer, String, MetaData, ForeignKey
+ [# K6 n: p: Q5 Vfrom sqlalchemy.orm import relation, mapper, sessionmaker
from sqlalchemy.sql import *
( E  ^! ?9 z+ i/ `from sqlalchemy.ext.associationproxy import association_proxy
log = logging.getLogger('nm_test')
, y5 m1 _7 q" f6 L" M! {logging.basicConfig(level=logging.DEBUG,
* L9 b/ D* I. c/ D! L0 H/ ?        format='%(asctime)s,%(msecs)03d %(levelname)s [%(filename)s.%(funcName)s @ %(lineno)d.%(thread)d] %(message)s')
engine = create_engine('sqlite:///:memory:', echo = False, echo_pool = False)
meta = MetaData()
* _6 j  d) \& _% [) I# emeta.bind = engine
developer_table = Table('developer', meta,
    Column('id', Integer, primary_key=True, autoincrement = False),
    Column('name', String),
)
6 c( ?% P) K7 \1 \: ]; |) a  Nproject_table = Table('project', meta,
    Column('id', Integer, primary_key=True, autoincrement = True),
    Column('name', String)
3 x) v; z" Y9 H0 a)
# {5 P- K9 c2 Vdeveloper_project_table = Table('developer_project', meta,
    Column('developer_id', Integer, ForeignKey('developer.id'), primary_key = True),
    Column('project_id', Integer, ForeignKey('project.id'), primary_key = True),
    Column('status', String)
3 v* ]/ W" b3 h)
& j. e4 _1 d& [, }! oclass Developer(object):
' U( l0 {: h3 d) w; ]& k    projects = association_proxy('developerProjects', 'projects')
    def __str__(self):
' _* d. f# u% \. m& U9 h        return 'Developer id:%i, name:%s' % (self.id, self.name)
class Project(object):
    developers = association_proxy('developerProjects', 'developers')
$ n* F6 U' p9 _: M6 O2 J$ d4 _    def __str__(self):
        return 'Project id:%i, name:%s' % (self.id, self.name)
class DeveloperProject(object):
    def __str__(self):
* w& {: H! e; ^3 ?2 w% c; Z3 n6 }        return 'DeveloperProject developer:%s, project:%s, status:%s' % (self.developer_id, self.project_id, self.status)
) K) m; R* X$ p( ~mapper(Developer, developer_table, properties = {
    'developerProjects':relation(DeveloperProject, backref = "developers")
})
- \' S. Q4 i0 u* {mapper(Project, project_table, properties = {
: x) N* w9 P7 P9 l    'developerProjects':relation(DeveloperProject, backref = "projects")
})
# j! v6 S, {  _: j1 e9 Imapper(DeveloperProject, developer_project_table)
# F; Z: _' n' G0 @, b5 `% w4 Pmeta.create_all(engine)
: v" `# g- u  a& X& L* dconn = engine.connect()
conn.execute(project_table.insert(),[
: L3 ^: _3 r3 V$ N    {'name':'stackoverflow'},
1 y) [; o: Z1 p2 S' I: n7 `4 A    {'name':'superuser'},
])
3 a( s  D" u9 _5 lconn.execute(developer_table.insert(),[
- {( R$ u* P9 T1 w/ s% o    {'name':'John'},
    {'name': 'TerryJ'},
    {'name': 'TerryG'},
    {'name': 'Eric'},
    {'name': 'Graham'},
])
conn.execute(developer_project_table.insert(),[
    {'developer_id':1, 'project_id':1, 'status':'active'},
    {'developer_id':2, 'project_id':2, 'status':'inactive'},
    {'developer_id':3, 'project_id':2, 'status':'active'},
  G5 a" Z8 r5 w$ j" k# ?    {'developer_id':4, 'project_id':1, 'status':'active'},
    {'developer_id':4, 'project_id':2, 'status':'active'},
    {'developer_id':5, 'project_id':1, 'status':'active'},
    {'developer_id':5, 'project_id':2, 'status':'inactive'},
])
Session = sessionmaker(bind=engine)
4 Y9 ~1 w% @9 i/ ^7 F0 @, is = Session()
: v8 O$ g1 M8 p$ C/ T/ ldevelopers = s.query(Developer).all()
  E/ K9 E" d. w1 b! _projects = s.query(Project).all()
for d in developers:
: C# g% ~* J2 n( J" i: K2 b+ `    log.debug(d)
    for p in d.projects:
        log.debug('    %s' % p)
' L4 `+ N  h, m( n9 Y* w0 w" Xfor p in projects:
    log.debug(p)
. |( _6 L. M: ~; M7 [9 Z  W    for d in p.developers:
        log.debug('    %s' % d)
5 t+ U2 Y5 V6 k* H# does not work
activeDevelopers = s.query(Developer).filter_by(Developer.developerProjects.status == 'active').all()
# AttributeError: Neither 'InstrumentedAttribute' object nor 'Comparator' object has an attribute 'status'
$ {2 q$ `! M6 S               
解决方案:
               

0 s9 n+ p2 }2 Q& y6 V
) E6 j; |- ?; h9 O1 p) }3 F                关联代理的使用any()方法：
5 j$ C4 n4 J- B4 gs.query(Developer).filter(Developer.developerProjects.any(status='active'))