SQLite; "Cannot add a PRIMARY KEY column"-Exception - c#

today I have started coping with databases. I've installed SQLite and SQLite-net. I am Programming a Windows 8.1 App using C#.
All I have is the following:
A Model:
public class Subject
{
[PrimaryKey, AutoIncrement]
public int Id { get; set; }
public string Name { get; set; }
}
And the OnLaunched-Event in App.Xaml.cs contains:
protected override void OnLaunched(LaunchActivatedEventArgs e)
{
[...]
// Get a reference to the SQLite database
DBPath = Path.Combine(
Windows.Storage.ApplicationData.Current.LocalFolder.Path, "Subjects.s3db");
// Initialize the database if necessary
using (var db = new SQLite.SQLiteConnection(DBPath))
{
// Create the tables if they don't exist
db.CreateTable<Subject>();
}
[...]
}
When I launch this I get the following error after db.CreateTable(); is executed:
Cannot add a PRIMARY KEY column.
What is going wrong here? I really would appreciate your help.
Thank you very much.
Greetings, FunkyPeanut


I believe this is happening because you've changed the schema of the DB table by adding or removing a field from your Subject class. I.e. you've added the Id property after having already run the application to create the Subject table.
This is why it works with a new DB file. You'll either need to modify the schema (which in SQLite involves creating a new table, copy data from the existing table, deleting existing table and then renaming the new table), or simply delete your old DB file and create a new one.


I had the same issue ... this is so stupid but it was because when I copied / pasted code from another table I forgot to change its name ......
Before
[Table("CopiedTable")]
After
[Table("MyNewTable")]


I had the same issue.
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