topic How to remove loosely coupled keys! in QlikView

How to remove loosely coupled keys!

Wed, 30 Jun 2010 06:19:47 GMT

Hi All,

There are several loosely coupled keys in our data model. I don't have any clue on how to avoid the same as I am not able to find where the circular loop is happening in my data model.

Can some one help me out how to find where the circular loop that is there in my data model and what i need to do to avoid the same.

How to remove loosely coupled keys!

Wed, 30 Jun 2010 09:13:16 GMT

Hi Rikab,

Look at the bottom center of the diagram where you can see one table with two variable linking (looks like a Hook). I think this is where the circular loop is happening.

Thanks,

Sajeevan

How to remove loosely coupled keys!

Wed, 30 Jun 2010 10:26:17 GMT

Hi Sajeevan,

Are you talking about the fsdivision table? It was added to avoid the synthetic key.

If you feel that is were the problem is then I am removing that table itself. Still there are many other loosely coupled keys persists in the data model.

Any idea where the circular loop is happening and how it can be removed.

By the way let me know how you got to know that fsdivision is creating the problem here.

Please do reply!

Many thanks for your help.

How to remove loosely coupled keys!

Wed, 30 Jun 2010 11:01:52 GMT

Hi Rikab,

Now, your circular loop is solved. Those links in the diagram with dotted links are the loosely coupled keys. I had faced this issue before but I don't remember how I solved that issue.

You can go to Settings/Document Properties/Tables and remove the tick marks on the loosely coupled. I don't know what will be the impact.

Thanks,

Sajeevan

How to remove loosely coupled keys!

Wed, 30 Jun 2010 11:08:05 GMT

Hi Rikab,

Please refer the QlikView reference manual for further explanation of circular reference and loosely coupled tables.

Thanks,

Sajeevan

How to remove loosely coupled keys!

Wed, 30 Jun 2010 12:09:33 GMT

Hi Sajeevan,

So you mean to say that as both the variable of the table is dotted it is circular? Am I right? Then what is loosely couple then?

These days I thought that both the circular reference key and loosely coupled key are same only. Please explain!

How to remove loosely coupled keys!

Wed, 30 Jun 2010 13:05:41 GMT

Hi Rikab,

Please read carefully!

The dotted is loosely coupled. The circular reference will have a Hook kind of linking - look at your first diagram bottom center.

Hope you are clear now.

Thanks,

Sajeevan

How to remove loosely coupled keys!

Wed, 30 Jun 2010 13:30:54 GMT

Hi Sajeevan,

I am not clear till now. I am able to find which is loosely coupled by seeing the dotted line. But I am not able to figure out which is circular reference there. It will be better if you can highlight in that picture.

Also I am not able to find out the difference between loosely coupled and circular reference. It will be great if you can explain me the same.

Thanks for your effort!

How to remove loosely coupled keys!

Wed, 30 Jun 2010 13:38:34 GMT

From your 1st Diagram

How to remove loosely coupled keys!

Wed, 30 Jun 2010 14:16:02 GMT

Hi Sajeevan,

First of all sorry for the trouble which I giving to you.

Please explain how you are saying that there is a circular reference there. I am not able to find it out.

How to remove loosely coupled keys!

Wed, 30 Jun 2010 14:23:17 GMT

Hi Rikab,

Since you have already removed the circular reference, how can you see that now? Are you currently getting any circular reference error?

Thanks,

Sajeevan

How to remove loosely coupled keys!

Wed, 30 Jun 2010 14:39:58 GMT

Hi Sajeevan,

No I never got the circular reference error previously also. I got below error which is supposed to be for loosely coupled if I am right.


One or more loops have been detected in your database structure. Loops may cause ambiguous results and should therefore be avoided. QlikView will cut the loop(s) by setting one or more tables as loosely coupled. Settings for loosely coupled tables can be modified after script execution in the tables page of the document properties dialog.

As I said then only I got to know that there is circular reference loop. Though I am not able to find it out where it is there exactly!

For your reference I have copied the same snapshot which is there with circular loop for your reference.

How to remove loosely coupled keys!

Wed, 30 Jun 2010 15:24:07 GMT

Hi Rikab,

Please ignore my earlier message on "circular referece".

The circular reference happens when you have many variables inter-linking between tables without an end. Some of the variables causing this are "fscode", "areacode", "subareacode", "poolcode" etc. Look at the diagram, check for "fscode" where it is starting the linking and where it is ending, then chek for any other variable is linking back to the same table.

Look at the diagram in detail - the "callindex" table is linking "fsmaster" table then linking "pooldetail" table with "fscode", then "pooldetail" table is linking "poolmaster" table with "poolcode", then "poolmaster" table is linking "fsmaster" table with "areacode" which is already linked with "callindex" table by "fascode". This link is not ending anywhere because the "fscode" in "fsmaster" will link back to "callindex" the linking repeats. This kind of linking is called "circular reference" since the inter-linking is keep on happening without an end to it.

Hope the above is good enough for you to understand. Don't ask me how to remove it - the removal is depended on how you want the end result.

Thanks,

Sajeevan

How to remove loosely coupled keys!

Sat, 03 Jul 2010 08:49:22 GMT

Hi Sajeevan,

Sure I will look into it. Yes I know I can't ask you to remove the unwanted things as it has to be removed by me only.

I have facing some problem here regarding the interval match. Can give me some time of yours when you are free.

http://community.qlik.com/forums/t/31016.aspx

http://community.qlik.com/forums/t/31125.aspx

http://community.qlik.com/forums/t/31095.aspx

Thanks and in advance