Contexts and Incompatible Objects

[ADB1]

All,

Please could someone briefly explain how contexts work. I understand their usage when it comes to resoving loops in a universe, but I am getting the error: Incompatible Objects (qp0004). I do not have any loops in my universe, but do have aliases. Why does adding a context to this series of joins solve the error?

Thanks in advance.

Adam.

 

[nimmy99]

There are incompatible objects in the universe and the universe designer did not set the option that allows multiple SQL statements for each context.

There are no contexts in the universe and the query has created a loop.

The query objects exclude all possible SQL choices for an aggregate aware function.

Take a look at this.

 

[skrandel]

My guess is that you have built an object that spans your contexts. That is not allowed.

For example, if you have an orders context and a sales context, you can't have an object that retrieves data from both the sales and orders fact tables.

Let me know if you want some information on contexts and when to use them.


Steve Krandel
Knightsbridge Solutions
formerly BASE Consulting Group

http://www.knightsbridge.com

 

[Sridharan]

Steve,

Shouldn't the Multiple Statement for each Context break the SQL into two if he picks up from Orders and Sales fact table.

Sri

 

[skrandel]

If you have 2 measures, BO will break the query into 2 SQL statements. If you have an object that uses columns from 2 tables that are in different contexts, BO doesn't know which query to put this object into. So, it can't do it.

Basically an object can be defined as a combination of columns from multiple tables, but those columns all have to exist in 1 context.

Steve Krandel
Knightsbridge Solutions
formerly BASE Consulting Group

http://www.knightsbridge.com

 

[Sridharan]

Steve wrote:

If you have 2 measures, BO will break the query into 2 SQL statements. If you have an object that uses columns from 2 tables that are in different contexts, BO doesn't know which query to put this object into. So, it can't do it.

Yeah I agree Steve.

Cheers
Sri

 

[vani65]

I prefer to resole loops by alias rather than context. If you have contextin universe user has to choose the write context where generally they get confused. So, i preferred alias -- am I correct Steve / Sri?

 

[Sridharan]

That is not the case always. If the user is prompted for the context then the context are not built properly. Infact if the loop is caused by a Fact Table use Context and if it is caused by a Dimension Table which can convey two different things (Customer, Supplier) then one can go for Alias.

Like Steve used to say Contexts are your best friend. Maybe you can request Steve to send the Context Vs Alias paper to you.

I'm sure Steve will have something to add more.

Sri

 

[vani65]

Hi Steve,
as Sri said "Maybe you can request Steve to send the Context Vs Alias paper to you."

i like to have that parep, could you please send it me:
vanivangala@hotmail.com

 

[skrandel]

Do I have something to add?!??!?!

If your contexts are prompting, you are building them wrong! A context should have something unique about it. That uniqueness is generally a fact table.

Aliases cause MUCH more confusion to the users since they have to guess at which objects to use.

If you want the context papers, send me an email.

Steve Krandel
Knightsbridge Solutions
formerly BASE Consulting Group

http://www.knightsbridge.com

 

[ameneon]

Hi Steve,

Could you please send the context papers to dagfinn_buzz@hotmail.com .

 

[vani65]

Hi Steve,
please send me the Context paper, my email:vanivangala@hotmail.com

 

[seanm95]

I would appreciate getting the paper as well. I am wrestling with contexts, fan traps, aliases, etc.

My email: seanm95 @ yahoo.com