private Iterator BuildJoin(BoundJoinRelation relation)
{
var left = BuildRelation(relation.Left);
_outerRowBufferAllocation = BuildRowBufferAllocation(relation.Left, left.RowBuffer);
var right = BuildRelation(relation.Right);
var combinedAllocation = BuildRowBufferAllocation(relation.Right, right.RowBuffer);
_outerRowBufferAllocation = _outerRowBufferAllocation.Parent;
var predicate = BuildPredicate(relation.Condition, true, combinedAllocation);
var passthruPredicate = BuildPredicate(relation.PassthruPredicate, false, combinedAllocation);
switch (relation.JoinType)
{
case BoundJoinType.Inner:
Debug.Assert(relation.Probe == null);
return(new InnerNestedLoopsIterator(left, right, predicate, passthruPredicate));
case BoundJoinType.LeftSemi:
return(relation.Probe == null
? (Iterator) new LeftSemiNestedLoopsIterator(left, right, predicate, passthruPredicate)
: new ProbingLeftSemiNestedLoopsIterator(left, right, predicate));
case BoundJoinType.LeftAntiSemi:
Debug.Assert(relation.Probe == null);
return(new LeftAntiSemiNestedLoopsIterator(left, right, predicate, passthruPredicate));
case BoundJoinType.LeftOuter:
return(new LeftOuterNestedLoopsIterator(left, right, predicate, passthruPredicate));
default:
throw ExceptionBuilder.UnexpectedValue(relation.JoinType);
}
}
public RowBufferAllocation(RowBufferAllocation parent, RowBuffer rowBuffer, IEnumerable <ValueSlot> valueSlots)
{
Parent = parent;
RowBuffer = rowBuffer;
_mapping = GetValueMapping(valueSlots.ToImmutableArray());
}
private static TDelegate BuildExpression <TDelegate>(BoundExpression expression, Type targetType, RowBufferAllocation allocation)
{
var builder = new ExpressionBuilder(allocation);
return(builder.BuildExpression <TDelegate>(expression, targetType));
}
public static IteratorPredicate BuildIteratorPredicate(BoundExpression predicate, bool nullValue, RowBufferAllocation allocation)
{
if (predicate == null)
{
return(() => nullValue);
}
return(BuildExpression <IteratorPredicate>(predicate, typeof(bool), allocation));
}
public static IteratorFunction BuildIteratorFunction(BoundExpression expression, RowBufferAllocation allocation)
{
return(BuildExpression <IteratorFunction>(expression, typeof(object), allocation));
}
private ExpressionBuilder(RowBufferAllocation allocation)
{
_rowBufferAllocation = allocation;
}
private static IteratorPredicate BuildPredicate(BoundExpression predicate, bool nullValue, RowBufferAllocation allocation)
{
return(ExpressionBuilder.BuildIteratorPredicate(predicate, nullValue, allocation));
}
private static IteratorFunction BuildFunction(BoundExpression expression, RowBufferAllocation allocation)
{
return(ExpressionBuilder.BuildIteratorFunction(expression, allocation));
}