Attribute table of GPKG layer does not allow to edit

Question

I created a GPKG layer whose name is Grid 1. In database, I wrote a trigger,because when attribute table of layer is changed, another table value should be changed also -They have common id's.

However, when I try to edit the attribute table, I can not edit it. Here is my update trigger code:

self.execSql("CREATE TRIGGER 'ibound_trigger1' AFTER UPDATE OF ibound ON 'Grid1' BEGIN UPDATE 'Yas_Veri' SET ibound = NEW.ibound WHERE cell_id = NEW.cell_id; END;")

Grid1: GPKG layer on canvas (triggers Yas_Veri table)

Yas_Veri: Table in my database (triggered from Grid1)

ibound : column name (common for both table)

Answer 1

It is because of primary key. The table has to have primary key.