def collectAndRemoveFilters(parts):
"""
FILTER expressions apply to the whole group graph pattern in which
they appear.
http://www.w3.org/TR/sparql11-query/#sparqlCollectFilters
"""
filters = []
i = 0
while i < len(parts):
p = parts[i]
if p.name == 'Filter':
filters.append(translateExists(p.expr))
parts.pop(i)
else:
i += 1
if filters:
return and_(*filters)
return None
def collectAndRemoveFilters(parts):
"""
FILTER expressions apply to the whole group graph pattern in which
they appear.
http://www.w3.org/TR/sparql11-query/#sparqlCollectFilters
"""
filters = []
i = 0
while i < len(parts):
p = parts[i]
if p.name == 'Filter':
filters.append(translateExists(p.expr))
parts.pop(i)
else:
i += 1
if filters:
return and_(*filters)
return None
def translate(q):
"""
http://www.w3.org/TR/sparql11-query/#convertSolMod
"""
_traverse(q, _simplifyFilters)
q.where = traverse(q.where, visitPost=translatePath)
# TODO: Var scope test
VS = set()
traverse(q.where, functools.partial(_findVars, res=VS))
# all query types have a where part
M = translateGroupGraphPattern(q.where)
aggregate = False
if q.groupby:
conditions = []
# convert "GROUP BY (?expr as ?var)" to an Extend
for c in q.groupby.condition:
if isinstance(c, CompValue) and c.name == "GroupAs":
M = Extend(M, c.expr, c.var)
c = c.var
conditions.append(c)
M = Group(p=M, expr=conditions)
aggregate = True
elif (traverse(q.having, _hasAggregate, complete=False)
or traverse(q.orderby, _hasAggregate, complete=False) or any(
traverse(x.expr, _hasAggregate, complete=False)
for x in q.projection or [] if x.evar)):
# if any aggregate is used, implicit group by
M = Group(p=M)
aggregate = True
if aggregate:
M, E = translateAggregates(q, M)
else:
E = []
# HAVING
if q.having:
M = Filter(expr=and_(*q.having.condition), p=M)
# VALUES
if q.valuesClause:
M = Join(p1=M, p2=ToMultiSet(translateValues(q.valuesClause)))
if not q.projection:
# select *
PV = list(VS)
else:
PV = list()
for v in q.projection:
if v.var:
if v not in PV:
PV.append(v.var)
elif v.evar:
if v not in PV:
PV.append(v.evar)
E.append((v.expr, v.evar))
else:
raise Exception("I expected a var or evar here!")
for e, v in E:
M = Extend(M, e, v)
# ORDER BY
if q.orderby:
M = OrderBy(
M,
[
CompValue("OrderCondition", expr=c.expr, order=c.order)
for c in q.orderby.condition
],
)
# PROJECT
M = Project(M, PV)
if q.modifier:
if q.modifier == "DISTINCT":
M = CompValue("Distinct", p=M)
elif q.modifier == "REDUCED":
M = CompValue("Reduced", p=M)
if q.limitoffset:
offset = 0
if q.limitoffset.offset is not None:
offset = q.limitoffset.offset.toPython()
if q.limitoffset.limit is not None:
M = CompValue("Slice",
p=M,
start=offset,
length=q.limitoffset.limit.toPython())
else:
M = CompValue("Slice", p=M, start=offset)
return M, PV
def translate(q):
"""
http://www.w3.org/TR/sparql11-query/#convertSolMod
"""
_traverse(q, _simplifyFilters)
q.where = traverse(q.where, visitPost=translatePath)
# TODO: Var scope test
VS = set()
traverse(q.where, functools.partial(_findVars, res=VS))
# all query types have a where part
M = translateGroupGraphPattern(q.where)
aggregate = False
if q.groupby:
conditions = []
# convert "GROUP BY (?expr as ?var)" to an Extend
for c in q.groupby.condition:
if isinstance(c, CompValue) and c.name == 'GroupAs':
M = Extend(M, c.expr, c.var)
c = c.var
conditions.append(c)
M = Group(p=M, expr=conditions)
aggregate = True
elif traverse(q.having, _hasAggregate, complete=False) or \
traverse(q.orderby, _hasAggregate, complete=False) or \
any(traverse(x.expr, _hasAggregate, complete=False)
for x in q.projection or [] if x.evar):
# if any aggregate is used, implicit group by
M = Group(p=M)
aggregate = True
if aggregate:
M, E = translateAggregates(q, M)
else:
E = []
# HAVING
if q.having:
M = Filter(expr=and_(*q.having.condition), p=M)
# VALUES
if q.valuesClause:
M = Join(p1=M, p2=ToMultiSet(translateValues(q.valuesClause)))
if not q.projection:
# select *
PV = list(VS)
else:
PV = list()
for v in q.projection:
if v.var:
if v not in PV:
PV.append(v.var)
elif v.evar:
if v not in PV:
PV.append(v.evar)
E.append((v.expr, v.evar))
else:
raise Exception("I expected a var or evar here!")
for e, v in E:
M = Extend(M, e, v)
# ORDER BY
if q.orderby:
M = OrderBy(M, [CompValue('OrderCondition', expr=c.expr,
order=c.order) for c in q.orderby.condition])
# PROJECT
M = Project(M, PV)
if q.modifier:
if q.modifier == 'DISTINCT':
M = CompValue('Distinct', p=M)
elif q.modifier == 'REDUCED':
M = CompValue('Reduced', p=M)
if q.limitoffset:
offset = 0
if q.limitoffset.offset != None:
offset = q.limitoffset.offset.toPython()
if q.limitoffset.limit != None:
M = CompValue('Slice', p=M, start=offset,
length=q.limitoffset.limit.toPython())
else:
M = CompValue('Slice', p=M, start=offset)
return M, PV