Entity Data Model Designer not showing tables

I also had a similar problem. But in my case, it was due to missing Primary Key in the selected table. So, I added a primary key, and updated the model from the Database. After that, I could see the table, and all the columns!

Open your edmx file in a text editor. If you see the tables in the file but not in the designer, try clearing out all the EntitySet nodes and EntityType nodes, save the file, then go back to Visual Studio and try the Update Model from Database again.

<edmx:StorageModels>
    <Schema Namespace="myModel.Store">
        <EntityContainer Name="MyModelStoreContainer">
            delete-> <EntitySet Name="Table1" ... />
            delete-> <EntitySet Name="Table2" ... />
        </EntityContainer>
            delete-> <EntityType Name="Table1">...</EntityType>
            delete-> <EntityType Name="Table2">...</EntityType>
  </Schema></edmx:StorageModels>