Python sqlite3.OperationalError: no such table:

Question

I am trying to store data about pupils at a school. I've done a few tables before, such as one for passwords and Teachers which I will later bring together in one program.

I have pretty much copied the create table function from one of these and changed the values to for the Pupil's information. It works fine on the other programs but I keep getting:

sqlite3.OperationalError: no such table: PupilPremiumTable

when I try to add a pupil to the table, it occurs on the line:

cursor.execute("select MAX(RecordID) from PupilPremiumTable")

I look in the folder and there is a file called PupilPremiumTable.db and the table has already been created before, so I don't know why it isn't working.

Here is some of my code, if you need more feel free to tell me so, as I said it worked before so I have no clue why it isn't working or even what isn't working:

with sqlite3.connect("PupilPremiumTable.db") as db:
    cursor = db.cursor()
    cursor.execute("select MAX(RecordID) from PupilPremiumTable")
    Value = cursor.fetchone()
    Value = str('.'.join(str(x) for x in Value))
    if Value == "None":
        Value = int(0)
    else:
        Value = int('.'.join(str(x) for x in Value))
    if Value == 'None,':
        Value = 0
    TeacherID = Value + 1
    print("This RecordID is: ",RecordID)

Answer 1

You are assuming that the current working directory is the same as the directory your script lives in. It is not an assumption you can make. Your script is opening a new database in a different directory, one that is empty.

Use an absolute path for your database file. You can base it on the absolute path of your script:

import os.path

BASE_DIR = os.path.dirname(os.path.abspath(__file__))
db_path = os.path.join(BASE_DIR, "PupilPremiumTable.db")
with sqlite3.connect(db_path) as db:

You can verify what the current working directory is with os.getcwd() if you want to figure out where instead you are opening the new database file; you probably want to clean up the extra file you created there.

Answer 2

I had the same problem and here's how I solved it.

1. I killed the server by pressing Ctrl+C
2. I deleted the pychache folder. You'll find this folder in your project folder.
3. I deleted the sqlite db.
4. I made migrations with python manage.py makemigrations <app_name> where <app_name> is the specific app that contains the model that's causing the error. In my case it was the mail app so I ran python manage.py makemigrations app.
5. I migrated in the normal way.
6. Then I started the server and it was all solved.

I believe the issue is as Jorge Cardenas said:

Maybe you are loading views or queries to database but you haven´t granted enough time for Django to migrate the models to DB. That's why the "table doesn't exist".

This solution is based on this youtube video

Answer 3

First, you need to check if that table 100% exist in the database. You can use sqlite viewer for that: https://inloop.github.io/sqlite-viewer/.

If the table exists, then you can write your table name in '', for example:

Select * from 'TableName'

Whatever your query is, I am just using Select * as an example.