Hi,

I'm having trouble with queries that seem simple enough to think about but hard to construct:

select * from table where id = max(id)

Is there any way to do this in the SelfService model without a GetScalar() followed by a GetMulti()?

Maybe another way to ask: How do I use an aggregate in an Expression?

I want to do something like

e = Expression(TableFieldIndex.Id, ExOp.Max);

filter.Add(PredicateFactory.CompareExpression(TableFieldIndex.Id,ComparisonOperator.Equal, e) );

benles wrote:

Hi,

I'm having trouble with queries that seem simple enough to think about but hard to construct:

select * from table where id = max(id)

Is there any way to do this in the SelfService model without a GetScalar() followed by a GetMulti()?

Maybe another way to ask: How do I use an aggregate in an Expression?

I want to do something like

e = Expression(TableFieldIndex.Id, ExOp.Max);

filter.Add(PredicateFactory.CompareExpression(TableFieldIndex.Id,ComparisonOperator.Equal, e) );

I think this will do the trick:

IEntityField idField = EntityFieldFactory.Create(TableFieldIndex.Id);
idField.AggregateFunctionToApply = AggregateFunction.Max;
filter.Add(PredicateFactory.CompareExpression(TableFieldIndex.Id, ComparisonOperator.Equal, new Expression(idField)) );