How to use a join in an update, say for example I have an update statement like this:

UPDATE R SET Score=(A.Weight*Q.Weight)/100 FROM Result R, Answer A , Questions Q WHERE ...

I am using LLBLGen Pro 2.6 with Adapter template group. Runtime library version is v2.0.50727 and the database is SQL server 2005 and .Net version is 2.0.

You should use UpdateEntitiesDirectly(), and define the joins as EntityRelations in the Relations collection property of the passed in relationPredicateBucket parameter.

I think I did not emphasize the actual problem....What I am not able to achieve is Score=(A.WeightQ.Weight)/100* part in the sample update statement in the original post. I think it is something trivial but I am lost

Try something like the following (improvised and not tested):

IExpression updateExpression1 = new Expression(AnswerFields.Weight, ExOp.Mul,
QuestionsFields.Weight);
IExpression updateExpression2 = new Expression(updateExpression1, ExOp.Div,
100);

ResultEntity result = new ResultEntity();

result.Fields[(int)ResultFieldIndex.Score].ExpressionToApply = updateExpression2;

DataAccessAdapter adapter = new DataAccessAdapter();
adapter.UpdateEntitiesDirectly(result, null);

Please check Expressions in entity updates

Thanks Walaa, it works fine. Before posting I did search in the help but failed to notice it