MerginMaps / MerginMaps/mobile

expression like "CASE WHEN "other_column" = 'no' THEN NULL END" work on QGIS, block/lock column on MM

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C++
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Description

Description

In a form in QGIS set the default value for a column as

CASE WHEN "other_column" = 'no' THEN NULL END

This works perfectly fine, if "other_column" value is set to "no" (in my case with a checkbox widget) then the content of the column where the default is applied is set/reset to NULL.

On the other hand on MM App this expression has the effect of blocking/locking the column, meaning that it turn as if was set to be not editable.

MM plugin 2026.3.0
MM App 2026.2.0

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Research direction

No source file, test, or entry point is identified in the report. Reproduce the expression in MM App 2026.2.0 with the QGIS project and compare it with QGIS behavior; done means the column remains editable and is reset to NULL when other_column is set to 'no'.

Written by the indexing model from the issue text.

Assessment

Tech stack
android, cpp, ios
Domain
mobile-dev
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Quiet
Clarity
Needs clarification
Newbie friendliness
42/100

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