Try to make an expression filter...ERROR

Question

I made a parameter with letter range values… put it into a dashboard filter. Then I created an expression filter to bind it to my last name column in the table with the image I uploaded here. I am getting the following error???

Invalid Expression. Validation of parameter values failed. A general error has occurred. Message returned from OBIS [ecid:f6ff0221-0f0b-4677-8a13-5280557eee49-000a0e54,0:3:2:4 ts:2026-09-10T11:33:11.696+00:00]. Near : Syntax error (HY000) . (HY000)

2026-09-10_07-38-31.png

Gianni Ceresa · Answer

Technically the BETWEEN with letters works, at least from a database query point of view (if your query is based on a dataset not stored in a database, that could have different limitation, but I expect it to fail with a different error showing you the physical query doesn't work if it's the case).

The issue I see is that you have a conditional block that you expect to use to return conditional expressions. The language doesn't allow that. Yours should be an expression, and the conditional block can't return "sub expressions" to be evaluated.

Turn your CASE WHEN … END into a filter expression without that CASE WHEN and it should be fine.

Something like this maybe…

(@parameter("p_Letter_Range")('ALL') = 'A to C' AND SUBSTRING(USR_LAST_NAME FROM 1 FOR 1) BETWEEN 'A' AND 'C'))

OR

(@parameter("p_Letter_Range")('ALL') = 'D to H' AND SUBSTRING(USR_LAST_NAME FROM 1 FOR 1) BETWEEN 'D' AND 'H'))

OR

(@parameter("p_Letter_Range")('ALL') NOT IN ('A to C', 'D to H'))

Daniel Ryan · Answer

Hi @User_SYYDG

I'm not 100% sure but I don't think you can use between with a text field. Have you tried using IN instead of BETWEEN?

Also, it doesn't look like you are filtering anything here and this is more of a conversion statement. What are you trying to limit the values to?