From d9f3b2a06370a88676afa91ff3cd73722ad38543 Mon Sep 17 00:00:00 2001 From: Mike Bayer Date: Sat, 25 Nov 2006 22:09:27 +0000 Subject: [PATCH] some clenaup on the "correlation" API on the _Select class --- lib/sqlalchemy/sql.py | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) diff --git a/lib/sqlalchemy/sql.py b/lib/sqlalchemy/sql.py index b5faf37fef..8605d5c0c5 100644 --- a/lib/sqlalchemy/sql.py +++ b/lib/sqlalchemy/sql.py @@ -1381,7 +1381,7 @@ class CompoundSelect(_SelectBaseMixin, FromClause): self.keyword = keyword self.use_labels = kwargs.pop('use_labels', False) self.parens = kwargs.pop('parens', False) - self.correlate = kwargs.pop('correlate', False) + self.should_correlate = kwargs.pop('correlate', False) self.for_update = kwargs.pop('for_update', False) self.nowait = kwargs.pop('nowait', False) self.limit = kwargs.pop('limit', None) @@ -1458,9 +1458,10 @@ class Select(_SelectBaseMixin, FromClause): # act like a single scalar column self.is_scalar = scalar - # indicates if this select statement, as a subquery, should correlate - # its FROM clause to that of an enclosing select statement - self.correlate = correlate + # indicates if this select statement, as a subquery, should automatically correlate + # its FROM clause to that of an enclosing select statement. + # note that the "correlate" method can be used to explicitly add a value to be correlated. + self.should_correlate = correlate # indicates if this select statement is a subquery inside another query self.is_subquery = False @@ -1471,7 +1472,7 @@ class Select(_SelectBaseMixin, FromClause): self.distinct = distinct self._raw_columns = [] - self._correlated = None + self.__correlated = {} self.__correlator = Select._CorrelatedVisitor(self, False) self.__wherecorrelator = Select._CorrelatedVisitor(self, True) @@ -1508,10 +1509,9 @@ class Select(_SelectBaseMixin, FromClause): select.is_where = self.is_where select.is_subquery = True select.parens = True - if not select.correlate: + if not select.should_correlate: return - if getattr(select, '_correlated', None) is None: - select._correlated = self.select._Select__froms + [select.correlate(x) for x in self.select._Select__froms] def append_column(self, column): if _is_literal(column): @@ -1548,9 +1548,13 @@ class Select(_SelectBaseMixin, FromClause): setattr(self, attribute, and_(getattr(self, attribute), condition)) else: setattr(self, attribute, condition) - - def clear_from(self, from_obj): - self.__froms[from_obj] = FromClause() + + def correlate(self, from_obj): + """given a FROM object, correlate this SELECT statement to it. + + this basically means the given from object will not come out in this select statement's FROM + clause when printed.""" + self.__correlated[from_obj] = from_obj def append_from(self, fromclause): if type(fromclause) == str: @@ -1569,7 +1573,7 @@ class Select(_SelectBaseMixin, FromClause): else: return None def _get_froms(self): - return [f for f in self.__froms.values() if f is not self and (self._correlated is None or not self._correlated.has_key(f))] + return [f for f in self.__froms.values() if f is not self and (f not in self.__correlated)] froms = property(lambda s: s._get_froms(), doc="""a list containing all elements of the FROM clause""") def accept_visitor(self, visitor): @@ -1635,7 +1639,7 @@ class _UpdateBase(ClauseElement): for key in parameters.keys(): value = parameters[key] if isinstance(value, Select): - value.clear_from(self.table) + value.correlate(self.table) elif _is_literal(value): if _is_literal(key): col = self.table.c[key] -- 2.47.2