totalCount error, number of items: 0 vs 1

Question

Hi! 
 I&acute;ve an error that I cannt resolve:

For this case, I load a grid with the data from my database. Then, I create a filter, and the error occurs when selecting a value that does not exist in the database for a column.

The query to the database returns 0 element and an empty list. But it seems that a record is loaded at null.


The code is:





And the ER answer:


Any idea where I could look?

Mike Schmitt · Accepted Answer

There's your issue. When you do " index(local!data, "columnName", null()) ", then when the data subset is empty it will return a single (null) value, causing the error you saw. What you would want to do instead is " index(local!data, "columnName", {}) " - as returning an empty set causes it to correctly show zero rows. ( a!forEach() smartly returns an empty set when the array it's given is empty, so it gets around this issue easily also.) (Incidentally, I also recommend using the property() function when pulling a named property from a CDT, and use index() when pulling an indexed position from an array. Both functions will work in either case, but it greatly helps readability of code in my experience when using them in the proper contexts. So it would be " property(local!data, "columnName", {}) ".)

Mike Schmitt · Answer

Is that query entity rule used in a lot of other places already? If not, I always suggest making a query entity rule optionally accept incoming pagingInfo data, and the way I do it is, when outside paging info was passed in, the expression rule returns the entire datasubset. This makes much more sense than querying ALL data, saving it in memory on the form, then paging over that on-form. Let me know if you need a recipe or something and I can try to find a generic example of what I mean.