SQL Expression Builder for the query widget is not loading unique values

Question

When configuring the SQL Expression Builder for the query widget, the unique values are not loading for any of the string fields. They are not loading in the SQL Expression Builder, or in the Query widget. The unique values are loading for other field types such as integer and date fields.  I am building this query for a feature service table published from a sde and it has around 400,000 features.

WR_TYPE is a string field, unique values will not load:

VERS is an integer field, unique values do load:

DanielGarcia · Answer

@Ke_Xu Is there any update on this topic?

Current Experience Builder in ArcGIS Online (February 2026) has the same issue. CHAR_LENGTH its only valid in service that use ArcGIS SQL syntax. According to the following article, if all layers in the service come from the same datasource location and this location is a Enterprise Database, the service use RBDMS Sintax for layer queries.

SQL reference for query expressions used in ArcGIS

Other possibility is that ArcGIS Server has been configured to avoid standardized queries

About standardized queries

atimmins · Answer

@Ke_Xu   Any update or patches on this?   I am seeing the issue in Enterprise 11.3 running ExB 1.14

Looking at he REST request, I can see the CHAR_LENGTH being used on a MS SQL box when LEN should be used.

kxu · Answer

Hi @NateWold1,

This is a known issue we currently have, related to CHAR_LENGTH() in the query expression. I will keep you updated.

Thanks,

Ke