QGIS » QGIS Application

In QGIS 3.2.1 on Windows 10, when attempting to add an empty layer from a SQL Server database using the Data Source Manager, the table's entry in the dialog becomes unselectable if its geometry type is set to "Polygon". As a result, the layer cannot be added.

No other geometry type seems to be affected.

To reproduce:

1. Create a basic table in SQL Server like the following. Importantly, do not add any records to the table, so the geometry type cannot be inferred by QGIS.
   

   CREATE TABLE [dbo].[Polygon] (
       [PolygonID] [int] IDENTITY(1, 1) NOT NULL,
       [Shape] [geometry]
   )
   

2. In QGIS, open the Data Source Manager (Ctrl-L), select "MSSQL" from the list on the left and connect to the database containing the table just created.
3. In the list of tables that appears, set the "Polygon" table's SRID to "4326" and its geometry type to "Polygon".
4. Attempt to select the table and add it to the project.

The issue appears to be a disagreement in the code on the meaning of the "Type" combo box's value: QgsMssqlSourceSelectDelegate::createEditor() populates it with values from the QgsWkbTypes::Type enum, while QgsMssqlTableModel::setData() interprets its value as belonging to the QgsWkbTypes::GeometryType enum. And since the value of QgsWkbTypes::Polygon happens to equal that of QgsWkbTypes::UnknownGeometry, setData() makes the table's entry unselectable when the "Polygon" type is selected in the UI.

This is probably the result of an edit accidentally left out of commit 4945611, which changed the enum used by QgsMssqlSourceSelectDelegate::createEditor().

I'll submit a pull request shortly.