cubicweb: comparison server/msplanner.py

equal deleted inserted replaced

-:308cf1eaf576
+:140d42b41b31
 except KeyError:
 continue # already proceed
 while sourceterms:
 # take a term randomly, and all terms supporting the
 # same solutions
-term, solindices = self._choose_term(sourceterms)
+term, solindices = self._choose_term(source, sourceterms)
 if source.uri == 'system':
 # ensure all variables are available for the latest step
 # (missing one will be available from temporary tables
 # of previous steps)
 scope = select
 # XXX already cleaned
 pass
 # set of terms which should be additionaly selected when
 # possible
 needsel = set()
-if not self._sourcesterms:
+if not self._sourcesterms and scope is select:
 terms += scope.defined_vars.values() + scope.aliases.values()
 if isinstance(term, Relation) and len(sources) > 1:
 variants = set()
 partterms = [term]
 for vref in term.get_nodes(VariableRef):
 if len(variants) == 2:
 # we need an extra-step to fetch relations from each source
 # before a join with prefetched inputs
 # (see test_crossed_relation_noeid_needattr in
 #  unittest_msplanner / unittest_multisources)
-needsel2 = needsel.copy()
-needsel2.update(variants)
 lhs, rhs = term.get_variable_parts()
 steps.append( (sources, [term, getattr(lhs, 'variable', lhs),
 getattr(rhs, 'variable', rhs)],
-solindices, scope,
+solindices, scope, variants, False) )
-needsel2, False) )
 sources = [self.system_source]
 final = True
 else:
 # suppose this is a final step until the contrary is proven
 final = scope is select
 needsel.add(vref.name)
 final = False
 break
 else:
 if not scope is select:
-self._exists_relation(rel, terms, needsel)
+self._exists_relation(rel, terms, needsel, source)
 # if relation is supported by all sources and some of
 # its lhs/rhs variable isn't in "terms", and the
 # other end *is* in "terms", mark it have to be
 # selected
 if source.uri != 'system' and not rschema(rel.r_type).final:
 break
 if final:
 self._cleanup_sourcesterms(sources, solindices)
 steps.append((sources, terms, solindices, scope, needsel, final)
 )
+if not steps[-1][-1]:
+# add a final step
+terms = select.defined_vars.values() + select.aliases.values()
+steps.append( ([self.system_source], terms, set(self._solindices),
+select, set(), True) )
 return steps
-def _exists_relation(self, rel, terms, needsel):
+def _exists_relation(self, rel, terms, needsel, source):
 rschema = self._schema.rschema(rel.r_type)
 lhs, rhs = rel.get_variable_parts()
 try:
 lhsvar, rhsvar = lhs.variable, rhs.variable
 except AttributeError:
 # supported relation with at least one end supported, check the
 # other end is in as well. If not this usually means the
 # variable is refed by an outer scope and should be substituted
 # using an 'identity' relation (else we'll get a conflict of
 # temporary tables)
-if rhsvar in terms and not lhsvar in terms and ms_scope(lhsvar) is lhsvar.stmt:
+relscope = ms_scope(rel)
-self._identity_substitute(rel, lhsvar, terms, needsel)
+lhsscope = ms_scope(lhsvar)
-elif lhsvar in terms and not rhsvar in terms and ms_scope(rhsvar) is rhsvar.stmt:
+rhsscope = ms_scope(rhsvar)
-self._identity_substitute(rel, rhsvar, terms, needsel)
+if rhsvar in terms and not lhsvar in terms and lhsscope is lhsvar.stmt:
+self._identity_substitute(rel, lhsvar, terms, needsel, relscope)
-def _identity_substitute(self, relation, var, terms, needsel):
+elif lhsvar in terms and not rhsvar in terms and rhsscope is rhsvar.stmt:
-newvar = self._insert_identity_variable(ms_scope(relation), var)
+self._identity_substitute(rel, rhsvar, terms, needsel, relscope)
+elif self.crossed_relation(source, rel):
+if lhsscope is not relscope:
+self._identity_substitute(rel, lhsvar, terms, needsel,
+relscope, lhsscope)
+if rhsscope is not relscope:
+self._identity_substitute(rel, rhsvar, terms, needsel,
+relscope, rhsscope)
+def _identity_substitute(self, relation, var, terms, needsel, exist,
+idrelscope=None):
+newvar = self._insert_identity_variable(exist, var, idrelscope)
 # ensure relation is using '=' operator, else we rely on a
 # sqlgenerator side effect (it won't insert an inequality operator
 # in this case)
 relation.children[1].operator = '='
 terms.append(newvar)
 needsel.add(newvar.name)
-def _choose_term(self, sourceterms):
+def _choose_term(self, source, sourceterms):
 """pick one term among terms supported by a source, which will be used
 as a base to generate an execution step
 """
 secondchoice = None
 if len(self._sourcesterms) > 1:
+# first, return non invariant variable of crossed relation, then the
+# crossed relation itself
+for term in sourceterms:
+if (isinstance(term, Relation)
+and self.crossed_relation(source, term)
+and not ms_scope(term) is self.rqlst):
+for vref in term.get_variable_parts():
+try:
+var = vref.variable
+except AttributeError:
+# Constant
+continue
+if ((len(var.stinfo['relations']) > 1 or var.stinfo['selected'])
+and var in sourceterms):
+return var, sourceterms.pop(var)
+return term, sourceterms.pop(term)
 # priority to variable from subscopes
 for term in sourceterms:
 if not ms_scope(term) is self.rqlst:
 if isinstance(term, Variable):
 return term, sourceterms.pop(term)

branch	stable
changeset 6794	140d42b41b31
parent 6759	5d016d5bacca
child 6943	406a41c25e13