Tpt
5 years ago
parent
9cc96a5155
commit
620b1c1df4
@ -0,0 +1,583 @@ |
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use crate::model::vocab::xsd; |
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use crate::model::Literal; |
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use crate::sparql::algebra::*; |
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use crate::sparql::model::*; |
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use crate::sparql::plan::*; |
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use crate::store::numeric_encoder::ENCODED_DEFAULT_GRAPH; |
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use crate::store::StoreConnection; |
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use crate::Result; |
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use failure::format_err; |
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pub struct PlanBuilder<'a, S: StoreConnection> { |
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store: &'a S, |
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} |
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impl<'a, S: StoreConnection> PlanBuilder<'a, S> { |
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pub fn build(store: &'a S, pattern: &GraphPattern) -> Result<(PlanNode, Vec<Variable>)> { |
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let mut variables = Vec::default(); |
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let plan = PlanBuilder { store }.build_for_graph_pattern( |
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pattern, |
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PlanNode::Init, |
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&mut variables, |
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PatternValue::Constant(ENCODED_DEFAULT_GRAPH), |
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)?; |
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Ok((plan, variables)) |
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} |
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pub fn build_graph_template( |
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store: &S, |
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template: &[TriplePattern], |
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mut variables: Vec<Variable>, |
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) -> Result<Vec<TripleTemplate>> { |
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PlanBuilder { store }.build_for_graph_template(template, &mut variables) |
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} |
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fn build_for_graph_pattern( |
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&self, |
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pattern: &GraphPattern, |
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input: PlanNode, |
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variables: &mut Vec<Variable>, |
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graph_name: PatternValue, |
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) -> Result<PlanNode> { |
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Ok(match pattern { |
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GraphPattern::BGP(p) => self.build_for_bgp(p, input, variables, graph_name)?, |
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GraphPattern::Join(a, b) => PlanNode::Join { |
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left: Box::new(self.build_for_graph_pattern( |
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a, |
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input.clone(), |
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variables, |
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graph_name, |
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)?), |
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right: Box::new(self.build_for_graph_pattern(b, input, variables, graph_name)?), |
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}, |
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GraphPattern::LeftJoin(a, b, e) => { |
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let left = self.build_for_graph_pattern(a, input, variables, graph_name)?; |
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let right = |
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self.build_for_graph_pattern(b, PlanNode::Init, variables, graph_name)?; |
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//We add the extra filter if needed
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let right = if *e == Expression::from(Literal::from(true)) { |
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right |
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} else { |
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PlanNode::Filter { |
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child: Box::new(right), |
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expression: self.build_for_expression(e, variables)?, |
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} |
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}; |
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let possible_problem_vars = right |
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.variables() |
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.difference(&left.variables()) |
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.cloned() |
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.collect(); |
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PlanNode::LeftJoin { |
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left: Box::new(left), |
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right: Box::new(right), |
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possible_problem_vars, |
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} |
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} |
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GraphPattern::Filter(e, p) => PlanNode::Filter { |
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child: Box::new(self.build_for_graph_pattern(p, input, variables, graph_name)?), |
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expression: self.build_for_expression(e, variables)?, |
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}, |
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GraphPattern::Union(a, b) => { |
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//We flatten the UNIONs
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let mut stack: Vec<&GraphPattern> = vec![a, b]; |
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let mut children = vec![]; |
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loop { |
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match stack.pop() { |
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None => break, |
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Some(GraphPattern::Union(a, b)) => { |
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stack.push(a); |
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stack.push(b); |
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} |
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Some(p) => children.push(self.build_for_graph_pattern( |
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p, |
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PlanNode::Init, |
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variables, |
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graph_name, |
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)?), |
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} |
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} |
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PlanNode::Union { |
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entry: Box::new(input), |
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children, |
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} |
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} |
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GraphPattern::Graph(g, p) => { |
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let graph_name = self.pattern_value_from_named_node_or_variable(g, variables)?; |
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self.build_for_graph_pattern(p, input, variables, graph_name)? |
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} |
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GraphPattern::Extend(p, v, e) => PlanNode::Extend { |
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child: Box::new(self.build_for_graph_pattern(p, input, variables, graph_name)?), |
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position: variable_key(variables, &v), |
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expression: self.build_for_expression(e, variables)?, |
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}, |
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GraphPattern::Minus(_a, _b) => unimplemented!(), |
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GraphPattern::Service(_n, _p, _s) => unimplemented!(), |
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GraphPattern::AggregateJoin(_g, _a) => unimplemented!(), |
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GraphPattern::Data(bs) => PlanNode::StaticBindings { |
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tuples: self.encode_bindings(bs, variables)?, |
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}, |
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GraphPattern::OrderBy(l, o) => { |
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let by: Result<Vec<_>> = o |
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.iter() |
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.map(|comp| match comp { |
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OrderComparator::Asc(e) => { |
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Ok(Comparator::Asc(self.build_for_expression(e, variables)?)) |
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} |
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OrderComparator::Desc(e) => { |
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Ok(Comparator::Desc(self.build_for_expression(e, variables)?)) |
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} |
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}) |
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.collect(); |
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PlanNode::Sort { |
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child: Box::new(self.build_for_graph_pattern(l, input, variables, graph_name)?), |
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by: by?, |
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} |
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} |
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GraphPattern::Project(l, new_variables) => PlanNode::Project { |
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child: Box::new(self.build_for_graph_pattern( |
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l, |
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input, |
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&mut new_variables.clone(), |
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graph_name, |
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)?), |
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mapping: new_variables |
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.iter() |
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.map(|variable| variable_key(variables, variable)) |
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.collect(), |
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}, |
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GraphPattern::Distinct(l) => PlanNode::HashDeduplicate { |
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child: Box::new(self.build_for_graph_pattern(l, input, variables, graph_name)?), |
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}, |
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GraphPattern::Reduced(l) => { |
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self.build_for_graph_pattern(l, input, variables, graph_name)? |
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} |
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GraphPattern::Slice(l, start, length) => { |
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let mut plan = self.build_for_graph_pattern(l, input, variables, graph_name)?; |
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if *start > 0 { |
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plan = PlanNode::Skip { |
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child: Box::new(plan), |
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count: *start, |
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}; |
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} |
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if let Some(length) = length { |
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plan = PlanNode::Limit { |
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child: Box::new(plan), |
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count: *length, |
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}; |
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} |
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plan |
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} |
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}) |
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} |
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fn build_for_bgp( |
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&self, |
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p: &[TripleOrPathPattern], |
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input: PlanNode, |
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variables: &mut Vec<Variable>, |
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graph_name: PatternValue, |
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) -> Result<PlanNode> { |
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let mut plan = input; |
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for pattern in p { |
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plan = match pattern { |
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TripleOrPathPattern::Triple(pattern) => PlanNode::QuadPatternJoin { |
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child: Box::new(plan), |
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subject: self |
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.pattern_value_from_term_or_variable(&pattern.subject, variables)?, |
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predicate: self |
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.pattern_value_from_named_node_or_variable(&pattern.predicate, variables)?, |
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object: self.pattern_value_from_term_or_variable(&pattern.object, variables)?, |
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graph_name, |
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}, |
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TripleOrPathPattern::Path(_pattern) => unimplemented!(), |
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} |
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} |
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Ok(plan) |
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} |
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fn build_for_expression( |
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&self, |
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expression: &Expression, |
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variables: &mut Vec<Variable>, |
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) -> Result<PlanExpression> { |
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Ok(match expression { |
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Expression::Constant(t) => match t { |
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TermOrVariable::Term(t) => { |
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PlanExpression::Constant(self.store.encoder().encode_term(t)?) |
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} |
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TermOrVariable::Variable(v) => PlanExpression::Variable(variable_key(variables, v)), |
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}, |
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Expression::Or(a, b) => PlanExpression::Or( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::And(a, b) => PlanExpression::And( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::Equal(a, b) => PlanExpression::Equal( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::NotEqual(a, b) => PlanExpression::NotEqual( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::Greater(a, b) => PlanExpression::Greater( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::GreaterOrEq(a, b) => PlanExpression::GreaterOrEq( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::Lower(a, b) => PlanExpression::Lower( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::LowerOrEq(a, b) => PlanExpression::LowerOrEq( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::In(e, l) => PlanExpression::In( |
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Box::new(self.build_for_expression(e, variables)?), |
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self.expression_list(l, variables)?, |
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), |
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Expression::NotIn(e, l) => PlanExpression::UnaryNot(Box::new(PlanExpression::In( |
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Box::new(self.build_for_expression(e, variables)?), |
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self.expression_list(l, variables)?, |
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))), |
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Expression::Add(a, b) => PlanExpression::Add( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::Sub(a, b) => PlanExpression::Sub( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::Mul(a, b) => PlanExpression::Mul( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::Div(a, b) => PlanExpression::Div( |
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Box::new(self.build_for_expression(a, variables)?), |
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Box::new(self.build_for_expression(b, variables)?), |
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), |
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Expression::UnaryPlus(e) => { |
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PlanExpression::UnaryPlus(Box::new(self.build_for_expression(e, variables)?)) |
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} |
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Expression::UnaryMinus(e) => { |
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PlanExpression::UnaryMinus(Box::new(self.build_for_expression(e, variables)?)) |
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} |
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Expression::UnaryNot(e) => { |
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PlanExpression::UnaryNot(Box::new(self.build_for_expression(e, variables)?)) |
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} |
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Expression::FunctionCall(function, parameters) => match function { |
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Function::Str => PlanExpression::Str(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::Lang => PlanExpression::Lang(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::LangMatches => PlanExpression::LangMatches( |
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Box::new(self.build_for_expression(¶meters[0], variables)?), |
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Box::new(self.build_for_expression(¶meters[1], variables)?), |
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), |
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Function::Datatype => PlanExpression::Datatype(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::IRI => PlanExpression::IRI(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::BNode => PlanExpression::BNode(match parameters.get(0) { |
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Some(e) => Some(Box::new(self.build_for_expression(e, variables)?)), |
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None => None, |
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}), |
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Function::Year => PlanExpression::Year(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::Month => PlanExpression::Month(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::Day => PlanExpression::Day(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::Hours => PlanExpression::Hours(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::Minutes => PlanExpression::Minutes(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::Seconds => PlanExpression::Seconds(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::UUID => PlanExpression::UUID(), |
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Function::StrUUID => PlanExpression::StrUUID(), |
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Function::Coalesce => { |
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PlanExpression::Coalesce(self.expression_list(¶meters, variables)?) |
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} |
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Function::If => PlanExpression::If( |
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Box::new(self.build_for_expression(¶meters[0], variables)?), |
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Box::new(self.build_for_expression(¶meters[1], variables)?), |
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Box::new(self.build_for_expression(¶meters[2], variables)?), |
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), |
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Function::StrLang => PlanExpression::StrLang( |
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Box::new(self.build_for_expression(¶meters[0], variables)?), |
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Box::new(self.build_for_expression(¶meters[1], variables)?), |
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), |
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Function::SameTerm => PlanExpression::SameTerm( |
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Box::new(self.build_for_expression(¶meters[0], variables)?), |
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Box::new(self.build_for_expression(¶meters[1], variables)?), |
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), |
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Function::IsIRI => PlanExpression::IsIRI(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::IsBlank => PlanExpression::IsBlank(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::IsLiteral => PlanExpression::IsLiteral(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::IsNumeric => PlanExpression::IsNumeric(Box::new( |
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self.build_for_expression(¶meters[0], variables)?, |
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)), |
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Function::Regex => PlanExpression::Regex( |
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Box::new(self.build_for_expression(¶meters[0], variables)?), |
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Box::new(self.build_for_expression(¶meters[1], variables)?), |
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match parameters.get(2) { |
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Some(flags) => Some(Box::new(self.build_for_expression(flags, variables)?)), |
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None => None, |
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}, |
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), |
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Function::Custom(name) => { |
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if *name == *xsd::BOOLEAN { |
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self.build_cast( |
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parameters, |
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PlanExpression::BooleanCast, |
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variables, |
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"boolean", |
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)? |
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} else if *name == *xsd::DOUBLE { |
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self.build_cast( |
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parameters, |
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PlanExpression::DoubleCast, |
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variables, |
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"double", |
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)? |
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} else if *name == *xsd::FLOAT { |
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self.build_cast(parameters, PlanExpression::FloatCast, variables, "float")? |
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} else if *name == *xsd::DECIMAL { |
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self.build_cast( |
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parameters, |
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PlanExpression::DecimalCast, |
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variables, |
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"decimal", |
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)? |
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} else if *name == *xsd::INTEGER { |
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self.build_cast( |
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parameters, |
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PlanExpression::IntegerCast, |
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variables, |
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"integer", |
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)? |
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} else if *name == *xsd::DATE { |
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self.build_cast(parameters, PlanExpression::DateCast, variables, "date")? |
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} else if *name == *xsd::TIME { |
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self.build_cast(parameters, PlanExpression::TimeCast, variables, "time")? |
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} else if *name == *xsd::DATE_TIME { |
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self.build_cast( |
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parameters, |
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PlanExpression::DateTimeCast, |
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variables, |
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"dateTime", |
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)? |
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} else if *name == *xsd::STRING { |
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self.build_cast( |
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parameters, |
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PlanExpression::StringCast, |
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|
variables, |
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"string", |
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)? |
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} else { |
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|
Err(format_err!("Not supported custom function {}", expression))? |
||||||
|
} |
||||||
|
} |
||||||
|
_ => unimplemented!(), |
||||||
|
}, |
||||||
|
Expression::Bound(v) => PlanExpression::Bound(variable_key(variables, v)), |
||||||
|
Expression::Exists(_) => unimplemented!(), |
||||||
|
}) |
||||||
|
} |
||||||
|
|
||||||
|
fn build_cast( |
||||||
|
&self, |
||||||
|
parameters: &[Expression], |
||||||
|
constructor: impl Fn(Box<PlanExpression>) -> PlanExpression, |
||||||
|
variables: &mut Vec<Variable>, |
||||||
|
name: &'static str, |
||||||
|
) -> Result<PlanExpression> { |
||||||
|
if parameters.len() == 1 { |
||||||
|
Ok(constructor(Box::new( |
||||||
|
self.build_for_expression(¶meters[0], variables)?, |
||||||
|
))) |
||||||
|
} else { |
||||||
|
Err(format_err!( |
||||||
|
"The xsd:{} casting takes only one parameter", |
||||||
|
name |
||||||
|
)) |
||||||
|
} |
||||||
|
} |
||||||
|
|
||||||
|
fn expression_list( |
||||||
|
&self, |
||||||
|
l: &[Expression], |
||||||
|
variables: &mut Vec<Variable>, |
||||||
|
) -> Result<Vec<PlanExpression>> { |
||||||
|
l.iter() |
||||||
|
.map(|e| self.build_for_expression(e, variables)) |
||||||
|
.collect() |
||||||
|
} |
||||||
|
|
||||||
|
fn pattern_value_from_term_or_variable( |
||||||
|
&self, |
||||||
|
term_or_variable: &TermOrVariable, |
||||||
|
variables: &mut Vec<Variable>, |
||||||
|
) -> Result<PatternValue> { |
||||||
|
Ok(match term_or_variable { |
||||||
|
TermOrVariable::Term(term) => { |
||||||
|
PatternValue::Constant(self.store.encoder().encode_term(term)?) |
||||||
|
} |
||||||
|
TermOrVariable::Variable(variable) => { |
||||||
|
PatternValue::Variable(variable_key(variables, variable)) |
||||||
|
} |
||||||
|
}) |
||||||
|
} |
||||||
|
|
||||||
|
fn pattern_value_from_named_node_or_variable( |
||||||
|
&self, |
||||||
|
named_node_or_variable: &NamedNodeOrVariable, |
||||||
|
variables: &mut Vec<Variable>, |
||||||
|
) -> Result<PatternValue> { |
||||||
|
Ok(match named_node_or_variable { |
||||||
|
NamedNodeOrVariable::NamedNode(named_node) => { |
||||||
|
PatternValue::Constant(self.store.encoder().encode_named_node(named_node)?) |
||||||
|
} |
||||||
|
NamedNodeOrVariable::Variable(variable) => { |
||||||
|
PatternValue::Variable(variable_key(variables, variable)) |
||||||
|
} |
||||||
|
}) |
||||||
|
} |
||||||
|
|
||||||
|
fn encode_bindings( |
||||||
|
&self, |
||||||
|
bindings: &StaticBindings, |
||||||
|
variables: &mut Vec<Variable>, |
||||||
|
) -> Result<Vec<EncodedTuple>> { |
||||||
|
let encoder = self.store.encoder(); |
||||||
|
let bindings_variables = bindings.variables(); |
||||||
|
bindings |
||||||
|
.values_iter() |
||||||
|
.map(move |values| { |
||||||
|
let mut result = vec![None; variables.len()]; |
||||||
|
for (key, value) in values.iter().enumerate() { |
||||||
|
if let Some(term) = value { |
||||||
|
result[variable_key(variables, &bindings_variables[key])] = |
||||||
|
Some(encoder.encode_term(term)?); |
||||||
|
} |
||||||
|
} |
||||||
|
Ok(result) |
||||||
|
}) |
||||||
|
.collect() |
||||||
|
} |
||||||
|
|
||||||
|
fn build_for_graph_template( |
||||||
|
&self, |
||||||
|
template: &[TriplePattern], |
||||||
|
variables: &mut Vec<Variable>, |
||||||
|
) -> Result<Vec<TripleTemplate>> { |
||||||
|
let mut bnodes = Vec::default(); |
||||||
|
template |
||||||
|
.iter() |
||||||
|
.map(|triple| { |
||||||
|
Ok(TripleTemplate { |
||||||
|
subject: self.template_value_from_term_or_variable( |
||||||
|
&triple.subject, |
||||||
|
variables, |
||||||
|
&mut bnodes, |
||||||
|
)?, |
||||||
|
predicate: self.template_value_from_named_node_or_variable( |
||||||
|
&triple.predicate, |
||||||
|
variables, |
||||||
|
&mut bnodes, |
||||||
|
)?, |
||||||
|
object: self.template_value_from_term_or_variable( |
||||||
|
&triple.object, |
||||||
|
variables, |
||||||
|
&mut bnodes, |
||||||
|
)?, |
||||||
|
}) |
||||||
|
}) |
||||||
|
.collect() |
||||||
|
} |
||||||
|
|
||||||
|
fn template_value_from_term_or_variable( |
||||||
|
&self, |
||||||
|
term_or_variable: &TermOrVariable, |
||||||
|
variables: &mut Vec<Variable>, |
||||||
|
bnodes: &mut Vec<Variable>, |
||||||
|
) -> Result<TripleTemplateValue> { |
||||||
|
Ok(match term_or_variable { |
||||||
|
TermOrVariable::Term(term) => { |
||||||
|
TripleTemplateValue::Constant(self.store.encoder().encode_term(term)?) |
||||||
|
} |
||||||
|
TermOrVariable::Variable(variable) => { |
||||||
|
if variable.has_name() { |
||||||
|
TripleTemplateValue::Variable(variable_key(variables, variable)) |
||||||
|
} else { |
||||||
|
TripleTemplateValue::BlankNode(variable_key(bnodes, variable)) |
||||||
|
} |
||||||
|
} |
||||||
|
}) |
||||||
|
} |
||||||
|
|
||||||
|
fn template_value_from_named_node_or_variable( |
||||||
|
&self, |
||||||
|
named_node_or_variable: &NamedNodeOrVariable, |
||||||
|
variables: &mut Vec<Variable>, |
||||||
|
bnodes: &mut Vec<Variable>, |
||||||
|
) -> Result<TripleTemplateValue> { |
||||||
|
Ok(match named_node_or_variable { |
||||||
|
NamedNodeOrVariable::NamedNode(term) => { |
||||||
|
TripleTemplateValue::Constant(self.store.encoder().encode_named_node(term)?) |
||||||
|
} |
||||||
|
NamedNodeOrVariable::Variable(variable) => { |
||||||
|
if variable.has_name() { |
||||||
|
TripleTemplateValue::Variable(variable_key(variables, variable)) |
||||||
|
} else { |
||||||
|
TripleTemplateValue::BlankNode(variable_key(bnodes, variable)) |
||||||
|
} |
||||||
|
} |
||||||
|
}) |
||||||
|
} |
||||||
|
} |
||||||
|
|
||||||
|
fn variable_key(variables: &mut Vec<Variable>, variable: &Variable) -> usize { |
||||||
|
match slice_key(variables, variable) { |
||||||
|
Some(key) => key, |
||||||
|
None => { |
||||||
|
variables.push(variable.clone()); |
||||||
|
variables.len() - 1 |
||||||
|
} |
||||||
|
} |
||||||
|
} |
||||||
|
|
||||||
|
fn slice_key<T: Eq>(slice: &[T], element: &T) -> Option<usize> { |
||||||
|
for (i, item) in slice.iter().enumerate() { |
||||||
|
if item == element { |
||||||
|
return Some(i); |
||||||
|
} |
||||||
|
} |
||||||
|
None |
||||||
|
} |
||||||
Loading…
Reference in new issue