6 Replies Latest reply on Jun 11, 2009 6:07 AM by willem67

# dwindling valuelists

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dwindling valuelists

### Post

I Ineed to master the technique of dwindling valuelists.

I have seen examples, but I do not understand the exact formulas that I need for the calculations.

The valuelists that I want to build consists only of texts (titles of painting). E.g. if one painting is sold; it should not come up in my list anymore.

Willem

• ###### 1. Re: dwindling valuelists

You should have a number field with a value of 1 ( can use a checkbox with value of 1 ) to identify if it is sold. Also create an unstored calc that just returns 1 (cKonstant).

Now you can have your relationship be additionally keyed on cKonstant  ≠  SoldFlag. Now your value list when using a relationship, should give you only the ones that are not sold.

• ###### 2. Re: dwindling valuelists
thank you, wever this is not completely the thing i need i believe... maybe, my example was not very good

I use portals and many to many relations. To avoid double entries in my portals I have been advised to use dwindling valuelists.

E.g: I have records of exhibitions. In this record I have a portal that can show the paintings that have been exhibited. Especially if the list of paintings is much lager than the portal, there is a risk for double or even triple entries.

Once an item has been selected for the portal, I would like it to disappear (or grey out or so) from the valuelist.

I have seen examples, but I do not understand how these have been formulated....

Willem

• ###### 3. Re: dwindling valuelists

See here for a good example of a dwindling value list.

http://fmforums.com/forum/showpost.php?post/274656/

The basics of it is this... A calculation returns all the records that are already SELECTED. Then a another relationship is created based on this calc field using the not equal to operator. So this should give you a list of records not already used... Does this help?

• ###### 4. Re: dwindling valuelists

Yes, this does help, because this is what I need to make myself.

However, I find it very hard to re-create what is done in the example. I cannot retrace the steps.

Are there any simple guidelines somewhere to read?

• ###### 5. Re: dwindling valuelists

The power is in the relationships... Think of it this way, one relationship is used to determine what records are related. This is then used to figure out what values have already been selected and returns them into a list within a calculation.

Now then this calculation is used in a new relationship with the not equal to to grab what hasnt been selected yet. Considering that if it were already used, it would have a related record, by using the not equal to, it should return a list of values not already used from the master list.

• ###### 6. Re: dwindling valuelists

I understand want you mean. But I do not like to copy the example without really understanding what I am doing.

Can you teach me how to figure out how to make the calculation of the list of the selected records?

(Would it be simpler if after calculation of the selected records one adds the script "show non-selected records"?)