I'm trying to migrate my Django project from using sqlite3 to using PostgreSQL. I've created the database for the project, but when I try to run `syncdb`, I get the following error:

```
django.db.utils.ProgrammingError: column "partial_value" cannot be cast automatically to type double precision
HINT: Specify a USING expression to perform the conversion.

```

The column is defined like this in the model:

```
partial_value = models.FloatField()

```

I tried searching for similar questions, but they seemed to be more about replacing field types.