public override void VisitJoinClause(Remotion.Linq.Clauses.JoinClause joinClause, QueryModel queryModel, int index)
{
_isInstanceQuery = false;
_queryBuilder.AddFromPart(joinClause);
var inner = SparqlGeneratorWhereExpressionTreeVisitor.GetSparqlExpression(joinClause.InnerKeySelector, _queryBuilder);
var outer = SparqlGeneratorWhereExpressionTreeVisitor.GetSparqlExpression(joinClause.OuterKeySelector, _queryBuilder);
if (inner is SelectVariableNameExpression && outer is SelectVariableNameExpression)
{
var innerVar = inner as SelectVariableNameExpression;
var outerVar = outer as SelectVariableNameExpression;
if (innerVar.BindingType == VariableBindingType.Literal ||
outerVar.BindingType == VariableBindingType.Literal)
{
_queryBuilder.AddFilterExpression(string.Format("(?{0}=?{1})", innerVar.Name, outerVar.Name));
}
else
{
_queryBuilder.AddFilterExpression(string.Format("(sameTerm(?{0}, ?{1}))", innerVar.Name, outerVar.Name));
}
}
else
{
throw new NotSupportedException(
String.Format("No support for joining expressions of type {0} and {1}", inner.NodeType,
outer.NodeType));
}
}
private string GetExpressionVariable(Expression expression)
{
if (expression is QuerySourceReferenceExpression)
{
var querySource = expression as QuerySourceReferenceExpression;
Expression mappedExpression;
_queryBuilder.TryGetQuerySourceMapping(querySource.ReferencedQuerySource, out mappedExpression);
if (mappedExpression is SelectVariableNameExpression)
return (mappedExpression as SelectVariableNameExpression).Name;
}
var selector = SparqlGeneratorWhereExpressionTreeVisitor.GetSparqlExpression(expression, _queryBuilder);
if (selector is SelectVariableNameExpression) return (selector as SelectVariableNameExpression).Name;
return null;
}
public override void VisitAdditionalFromClause(Remotion.Linq.Clauses.AdditionalFromClause fromClause, QueryModel queryModel, int index)
{
_isInstanceQuery = false;
var fromVar = _queryBuilder.AddFromPart(fromClause);
if (!(fromClause.FromExpression is ConstantExpression))
{
var fromExpression =
SparqlGeneratorWhereExpressionTreeVisitor.GetSparqlExpression(fromClause.FromExpression,
_queryBuilder);
if (fromExpression is SelectVariableNameExpression)
{
_queryBuilder.RenameVariable((fromExpression as SelectVariableNameExpression).Name,fromVar);
}
}
base.VisitAdditionalFromClause(fromClause, queryModel, index);
}
public override void VisitOrdering(Remotion.Linq.Clauses.Ordering ordering, QueryModel queryModel, Remotion.Linq.Clauses.OrderByClause orderByClause, int index)
{
_isInstanceQuery = false;
var selector = SparqlGeneratorWhereExpressionTreeVisitor.GetSparqlExpression(ordering.Expression,
_queryBuilder);
if (selector is SelectVariableNameExpression)
{
var selectorVar = selector as SelectVariableNameExpression;
_queryBuilder.AddOrdering(new SparqlOrdering("?" + selectorVar.Name, ordering.OrderingDirection));
}
else
{
throw new NotSupportedException(
String.Format("LINQ-to-SPARQL does not currently support ordering by the expression '{0}'", ordering.Expression));
}
base.VisitOrdering(ordering, queryModel, orderByClause, index);
}
private string GetExpressionVariable(Expression expression)
{
if (expression is QuerySourceReferenceExpression)
{
var querySource = expression as QuerySourceReferenceExpression;
Expression mappedExpression;
_queryBuilder.TryGetQuerySourceMapping(querySource.ReferencedQuerySource, out mappedExpression);
if (mappedExpression is SelectVariableNameExpression)
{
return((mappedExpression as SelectVariableNameExpression).Name);
}
}
var selector = SparqlGeneratorWhereExpressionTreeVisitor.GetSparqlExpression(expression, _queryBuilder, _context.FilterOptimizationEnabled);
if (selector is SelectVariableNameExpression)
{
return((selector as SelectVariableNameExpression).Name);
}
return(null);
}
public override void VisitWhereClause(Remotion.Linq.Clauses.WhereClause whereClause, QueryModel queryModel, int index)
{
SparqlGeneratorWhereExpressionTreeVisitor.GetSparqlExpression(whereClause.Predicate, _queryBuilder);
base.VisitWhereClause(whereClause, queryModel, index);
}