Django: Using an F expression for a text field in an update call

Question

In a django view, I need to append string data to the end of an existing text column in my database. So, for example, say I have a table named \"ATable\", and it has a fiel

Answer 1

You can achieve this functionality with Django's select_for_update() operator: https://docs.djangoproject.com/en/dev/ref/models/querysets/#select-for-update

Something like this:

obj = ATable.objects.select_for_update().get(id=100)
obj.aField = obj.aField + aStringVar
obj.save()

The table row will be locked when you call .select_for_update().get(), and the lock will be released when you call .save(), allowing you to perform the operation atomically.