private TranslatedQuery PrepareSubqueryParameters(SubQueryExpression subQueryExpression, out Parameter <Tuple> parameterOfTuple, out Type elementType, out ProjectionExpression projection)
{
// 1. Rewrite recordset and ItemProjector to parameter<tuple>
var subqueryTupleParameter = context.GetTupleParameter(subQueryExpression.OuterParameter);
var newDataSource = ApplyParameterToTupleParameterRewriter.Rewrite(
subQueryExpression.ProjectionExpression.ItemProjector.DataSource,
subqueryTupleParameter,
subQueryExpression.ApplyParameter);
var newItemProjectorBody = ApplyParameterToTupleParameterRewriter.Rewrite(
subQueryExpression.ProjectionExpression.ItemProjector.Item,
subqueryTupleParameter,
subQueryExpression.ApplyParameter);
var itemProjector = new ItemProjectorExpression(newItemProjectorBody, newDataSource, subQueryExpression.ProjectionExpression.ItemProjector.Context);
parameterOfTuple = context.GetTupleParameter(subQueryExpression.OuterParameter);
// 2. Add only parameter<tuple>. Tuple value will be assigned
// at the moment of materialization in SubQuery constructor
projection = new ProjectionExpression(
subQueryExpression.ProjectionExpression.Type,
itemProjector,
subQueryExpression.ProjectionExpression.TupleParameterBindings,
subQueryExpression.ProjectionExpression.ResultType);
// 3. Make translation
elementType = subQueryExpression.ProjectionExpression.ItemProjector.Item.Type;
var resultType = SequenceHelper.GetSequenceType(elementType);
var translateMethod = Translator.TranslateMethod.MakeGenericMethod(new[] { resultType });
return((TranslatedQuery)translateMethod.Invoke(context.Translator, new object[] { projection, tupleParameters.AddOne(parameterOfTuple) }));
}
public static MaterializationInfo MakeMaterialization(ItemProjectorExpression projector, TranslatorContext context,
IEnumerable <Parameter <Tuple> > tupleParameters)
{
var tupleParameter = Expression.Parameter(typeof(Tuple), "tuple");
var materializationContextParameter = Expression.Parameter(typeof(ItemMaterializationContext), "mc");
var visitor = new ExpressionMaterializer(tupleParameter, context, materializationContextParameter, tupleParameters);
var lambda = FastExpression.Lambda(visitor.Visit(projector.Item), tupleParameter, materializationContextParameter);
var count = visitor.entityRegistry.Count;
return(new MaterializationInfo(count, lambda));
}
protected override Expression VisitProjectionExpression(ProjectionExpression projectionExpression)
{
var item = Visit(projectionExpression.ItemProjector.Item);
var provider = providerVisitor.VisitCompilable(projectionExpression.ItemProjector.DataSource);
var providerChanged = provider != projectionExpression.ItemProjector.DataSource;
var itemChanged = item != projectionExpression.ItemProjector.Item;
if (providerChanged || itemChanged)
{
var itemProjector = new ItemProjectorExpression(item, provider, projectionExpression.ItemProjector.Context);
return(new ProjectionExpression(
projectionExpression.Type,
itemProjector,
projectionExpression.TupleParameterBindings,
projectionExpression.ResultAccessMethod));
}
return(projectionExpression);
}
protected override Expression VisitSubQueryExpression(SubQueryExpression expression)
{
var newProvider = Rewrite(expression.ProjectionExpression.ItemProjector.DataSource, parameterOfTuple, applyParameter);
var newItemProjectorBody = Visit(expression.ProjectionExpression.ItemProjector.Item);
if (newProvider != expression.ProjectionExpression.ItemProjector.DataSource || newItemProjectorBody != expression.ProjectionExpression.ItemProjector.Item)
{
var newItemProjector = new ItemProjectorExpression(newItemProjectorBody, newProvider, expression.ProjectionExpression.ItemProjector.Context);
var newProjectionExpression = new ProjectionExpression(
expression.ProjectionExpression.Type,
newItemProjector,
expression.ProjectionExpression.TupleParameterBindings,
expression.ProjectionExpression.ResultType);
return(new SubQueryExpression(
expression.Type, expression.OuterParameter,
expression.DefaultIfEmpty, newProjectionExpression,
expression.ApplyParameter, expression.ExtendedType));
}
return(expression);
}
private ProjectionExpression GetIndexBinding(LambdaExpression le, ref ProjectionExpression sequence)
{
if (le.Parameters.Count == 2)
{
var indexDataSource = sequence.ItemProjector.DataSource.RowNumber(context.GetNextColumnAlias());
var columnExpression = ColumnExpression.Create(typeof(long), indexDataSource.Header.Columns.Count - 1);
var indexExpression = Expression.Subtract(columnExpression, Expression.Constant(1l));
var itemExpression = Expression.Convert(indexExpression, typeof(int));
var indexItemProjector = new ItemProjectorExpression(itemExpression, indexDataSource, context);
var indexProjectionExpression = new ProjectionExpression(typeof(long), indexItemProjector, sequence.TupleParameterBindings);
var sequenceItemProjector = sequence.ItemProjector.Remap(indexDataSource, 0);
sequence = new ProjectionExpression(
sequence.Type,
sequenceItemProjector,
sequence.TupleParameterBindings,
sequence.ResultType);
return(indexProjectionExpression);
}
return(null);
}
protected override Expression VisitGroupingExpression(GroupingExpression expression)
{
var newProvider = Rewrite(expression.ProjectionExpression.ItemProjector.DataSource, oldApplyParameter, newApplyParameter);
var newItemProjectorBody = Visit(expression.ProjectionExpression.ItemProjector.Item);
var newKeyExpression = Visit(expression.KeyExpression);
if (newProvider != expression.ProjectionExpression.ItemProjector.DataSource ||
newItemProjectorBody != expression.ProjectionExpression.ItemProjector.Item ||
newKeyExpression != expression.KeyExpression)
{
var newItemProjector = new ItemProjectorExpression(newItemProjectorBody, newProvider, expression.ProjectionExpression.ItemProjector.Context);
var newProjectionExpression = new ProjectionExpression(
expression.ProjectionExpression.Type,
newItemProjector,
expression.ProjectionExpression.TupleParameterBindings,
expression.ProjectionExpression.ResultType);
return(new GroupingExpression(
expression.Type, expression.OuterParameter, expression.DefaultIfEmpty, newProjectionExpression,
expression.ApplyParameter, expression.KeyExpression, expression.SelectManyInfo));
}
return(expression);
}
protected override Expression VisitItemProjectorExpression(ItemProjectorExpression itemProjectorExpression)
{
throw Exceptions.InternalError(String.Format(Strings.ExXDoesNotSupportX, typeof(PersistentExpressionVisitor), typeof(ItemProjectorExpression)), OrmLog.Instance);
}
public ItemProjectorExpression GetBoundItemProjector(ParameterExpression parameter, ItemProjectorExpression itemProjector)
{
ItemProjectorExpression result;
if (!boundItemProjectors.TryGetValue(parameter, out result))
{
result = itemProjector.BindOuterParameter(parameter);
boundItemProjectors.Add(parameter, result);
}
return(result);
}
protected virtual Expression VisitItemProjectorExpression(ItemProjectorExpression itemProjectorExpression)
{
return(itemProjectorExpression);
}
private EntityExpressionJoiner(Translator translator, ItemProjectorExpression itemProjectorExpression)
{
this.translator = translator;
this.itemProjectorExpression = itemProjectorExpression;
}
public static ItemProjectorExpression JoinEntities(Translator translator, ItemProjectorExpression itemProjectorExpression)
{
var item = new EntityExpressionJoiner(translator, itemProjectorExpression).Visit(itemProjectorExpression.Item);
return(new ItemProjectorExpression(item, itemProjectorExpression.DataSource, itemProjectorExpression.Context));
}
