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  3. sqlalchemy.sql.expression.Join()

Python sqlalchemy.sql.expression 模块，Join() 实例源码

我们从Python开源项目中，提取了以下26个代码示例，用于说明如何使用sqlalchemy.sql.expression.Join()。

项目：Flask_Blog    作者：sugarguo    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：QXSConsolas    作者：qxsch    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：flasky    作者：RoseOu    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：oa_qian    作者：sunqb    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：chihu    作者：yelongyu    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：ShelbySearch    作者：Agentscreech    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：pyetje    作者：rorlika    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if binary.left.table is join.right:
                            binary.left = _OuterJoinColumn(binary.left)
                        elif binary.right.table is join.right:
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(join.onclause, {},
                                {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Price-Comparator    作者：Thejas-1    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Flask-NvRay-Blog    作者：rui7157    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Flask-NvRay-Blog    作者：rui7157    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Callandtext    作者：iaora    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：python_ddd_flask    作者：igorvinnicius    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：webapp    作者：superchilli    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：QualquerMerdaAPI    作者：tiagovizoto    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：gardenbot    作者：GoestaO    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：flask-zhenai-mongo-echarts    作者：Fretice    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Data-visualization    作者：insta-code1    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：micro-blog    作者：nickChenyx    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：python-flask-security    作者：weinbergdavid    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：watcher    作者：nosmokingbandit    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Lixiang_zhaoxin    作者：hejaxian    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：flask    作者：bobohope    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Chorus    作者：DonaldBough    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Hawkeye    作者：tozhengxq    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：Alfred    作者：jkachhadia    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)
项目：ngx_status    作者：YoYoAdorkable    | 项目源码 | 文件源码 
def _get_nonansi_join_whereclause(self, froms):
        clauses = []

        def visit_join(join):
            if join.isouter:
                def visit_binary(binary):
                    if binary.operator == sql_operators.eq:
                        if join.right.is_derived_from(binary.left.table):
                            binary.left = _OuterJoinColumn(binary.left)
                        elif join.right.is_derived_from(binary.right.table):
                            binary.right = _OuterJoinColumn(binary.right)
                clauses.append(visitors.cloned_traverse(
                    join.onclause, {}, {'binary': visit_binary}))
            else:
                clauses.append(join.onclause)

            for j in join.left, join.right:
                if isinstance(j, expression.Join):
                    visit_join(j)
                elif isinstance(j, expression.FromGrouping):
                    visit_join(j.element)

        for f in froms:
            if isinstance(f, expression.Join):
                visit_join(f)

        if not clauses:
            return None
        else:
            return sql.and_(*clauses)