public override DbExpression Visit(DbJoinExpression expression)
{
Check.NotNull(expression, "expression");
DbExpression result = expression;
var newLeft = VisitExpressionBinding(expression.Left);
var newRight = VisitExpressionBinding(expression.Right);
EnterScope(newLeft.Variable, newRight.Variable);
var newCondition = VisitExpression(expression.JoinCondition);
ExitScope();
if (!ReferenceEquals(expression.Left, newLeft)
||
!ReferenceEquals(expression.Right, newRight)
||
!ReferenceEquals(expression.JoinCondition, newCondition))
{
if (DbExpressionKind.InnerJoin
== expression.ExpressionKind)
{
result = CqtBuilder.InnerJoin(newLeft, newRight, newCondition);
}
else if (DbExpressionKind.LeftOuterJoin
== expression.ExpressionKind)
{
result = CqtBuilder.LeftOuterJoin(newLeft, newRight, newCondition);
}
else
{
Debug.Assert(
expression.ExpressionKind == DbExpressionKind.FullOuterJoin,
"DbJoinExpression had ExpressionKind other than InnerJoin, LeftOuterJoin or FullOuterJoin?");
result = CqtBuilder.FullOuterJoin(newLeft, newRight, newCondition);
}
}
NotifyIfChanged(expression, result);
return(result);
}