The Listed Dimension Order in Rules

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tm1expert
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The Listed Dimension Order in Rules

Post by tm1expert »

Hi,

I have a question regarding the performance impact of Dimension Order in the Rules. The question is not related with the Order the Dimensions should be in the Cube, but with the Order you list elements from different dimensions in a Rule. TM1 Does not complain if in a psecific Rule Statement, the order of elements from different dimensions is not the same as the order of respective dimensions in Server Explorer.

So the following Rules for example:

['Master Version','Productivity'] = N: (Expression);
vs.
['Productivity','Master Version'] = N: (Expression);

They both work, but if the second one is in the same order with Dimension orders in Server Explorer, does it matter in the rules (Other than the rule becomes more readable)?

Does this fact have any impact on the performance?

Thank you
Ardian Alikaj
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qml
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Re: The Listed Dimension Order in Rules

Post by qml »

tm1expert wrote:They both work, but if the second one is in the same order with Dimension orders in Server Explorer, does it matter in the rules (Other than the rule becomes more readable)?
Not when using the shorthand notation with square brackets, as long as all listed elements are unique among all the dimensions used in the cube. If they are not unique then you need to prefix the repeating element names with dimension names.
tm1expert wrote:Does this fact have any impact on the performance?
Not to my knowledge and not from my experience. Personally, I like to have the order of elements in the shorthand rule syntax correspond to dimension ordering to keep things tidy, but it's not required for performance reasons.
Kamil Arendt
tm1expert
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Re: The Listed Dimension Order in Rules

Post by tm1expert »

Thank you qml,

I was hoping that re-ordering my elements would help because I'm dealing with Performance Issues in Rules and I'm trying to find ways to improve the performance.

Anyways, thanks a lot
Ardian Alikaj
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Re: The Listed Dimension Order in Rules

Post by Kaveenga »

Have you timed the outputs using the different orders?

I doubt whether changing the dimension order of the area defined in the LHS will impact performance.
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