Using QGIS 2.10.1 Pisa / PostgreSQL 9.4 with PostGIS.
In PostgreSQL I have column oid with datatype is bigINT as primary key. These are 16-digit numbers.
In QGIS I can read the table as a layer and view it. If i use the Identify tool, it shows all attributes in the Identify Results Window. In this Window I have set the option auto open form. Normaly if I now use the Identify tool a form opens and show the attributes as a form.
With this table the form does not open. If I change the datatype of the primary key to int, with a 8-digit number, QGIS shows me the form as expected.
I need to use bigInt datatype for my primary keys and I need to show the forms.