Issue 329 in dblinq2007: ?? Operator in Column Expression of Join wont work

[dblin...@googlecode.com]

Status: New
Owner: ----

New issue 329 by sauer1...@gmail.com: ?? Operator in Column Expression of
Join wont work
http://code.google.com/p/dblinq2007/issues/detail?id=329

What steps will reproduce the problem?
1. make query like this:
var query = from order in db.Order //can be null
join customer in db.Customer on (order.CustomerID??0)equals
customer.CustomerID
select new MyJoinedObject{ order=order, customer=customer };

What is the expected output?
data of Joined Tables

What do you see instead?
Exception: Error.BadArgument("S0701: No way to find left table for Join");
in DbLinq.Data.Linq.Sugar.Implementation.ExpressionDispatcher.AnalyzeJoin

What version of the product are you using? On what operating system?
rev 1411 on 7x64 .Net4, also happens on previous Version 0.20.1

Please provide any additional information below.
DB Looks like this:
+---------------+
+-------------------+ |Orders |
|Customer | +---------------+
+-------------------+ |int #OrderID |
|int #CustomerID | --> |int? CustomerID|
|string CustomerName| +---------------+
+-------------------+

Fixed it like this: (not good but works (for me))
private Expression AnalyzeJoin(IList<Expression> parameters, TableJoinType
joinType, BuilderContext builderContext)
{
if (parameters.Count == 5)
{
var leftExpression = Analyze(parameters[0], builderContext);
var rightTable = Analyze(parameters[1], builderContext) as
TableExpression;
if (rightTable == null)
throw Error.BadArgument("S0536: Expected a TableExpression for
Join");
var leftJoin = Analyze(parameters[2], leftExpression,
builderContext);
var rightJoin = Analyze(parameters[3], rightTable, builderContext);
// from here, we have two options to join:
// 1. left and right are tables, we can use generic expressions
(most common)
// 2. left is something else (a meta table)
var leftTable = leftExpression as TableExpression;
if (leftTable == null)
{
TableExpression table;
if (leftJoin.NodeType == ExpressionType.Coalesce)
table =
((ColumnExpression)((BinaryExpression)leftJoin).Left).Table;
else if (leftJoin.NodeType ==
((ExpressionType)CustomExpressionType.Column))
table = ((ColumnExpression)leftJoin).Table;
else
throw Error.BadArgument("S0701: No way to find left table for
Join");
leftTable= table;
}
rightTable.Join(joinType, leftTable, Expression.Equal(leftJoin,
rightJoin),
string.Format("join{0}",
builderContext.EnumerateAllTables().Count()));
// last part is lambda, with two tables as parameters
var metaTableDefinitionBuilderContext = builderContext.Clone();
metaTableDefinitionBuilderContext.ExpectMetaTableDefinition = true;
var expression = Analyze(parameters[4], new[] { leftExpression,
rightTable }, metaTableDefinitionBuilderContext);
return expression;
}
throw Error.BadArgument("S0530: Don't know how to handle GroupJoin()
with {0} parameters", parameters.Count);
}

[dblin...@googlecode.com]

Comment #1 on issue 329 by sauer1...@gmail.com: ?? Operator in Column

Expression of Join wont work
http://code.google.com/p/dblinq2007/issues/detail?id=329

Seems to be a dupe of 248, sry