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Invalid object name gets returned for certain databases in MS SQL Server Management Studio

I can connect to databases in MS SQL Server Management Studio using my python script without issues (using pyodbc).
I then created a database called tempdb - see the db explorer pic referred to below. I did this by running a direct query in MS SQL Management Studio, and created a table (DepartmentTest)
Now, in my script if I do:
cursor.execute("SELECT * FROM DepartmentTest")
I get:
[Microsoft][ODBC SQL Server Driver][SQL Server]Invalid object name
Also tried: a few options for the above query such as:
dbo.DepartmentTest
[dbo].DepartmentTest
(instead of just DepartmentTest as above.)
I don't have this issue when connecting to the master database and accessing the tables in the master database
e.g. I can execute:
cursor.execute("SELECT * FROM MSreplication_options")
and I get back the contents. I.e. anything under System Tables works fine with the script.
In the explorer pic referred to below: I can access the tables circled in green. I can't access my table, circled in red.
I assume I am not correctly pointing to my table with the syntax I am using, but I'm not sure how to modify my query. (it's as though anything under System Tables is fine to access with my code.
(I did connect to the correct database name with my code)
Thanks and
regards

You should double check you’re connected to the right database, which is suppose to be ‘tempdb’. If you do that and try running the query again, it should work.

It seems as though the trusted connection to the server was the problem. Once I did a connection with user and password credentials, I was able to access that database.

Using two databases with Pyramid SqlAlchemy

I have a SQLite database configured with Pyramid Alchemy scaffold in my Linux machine. I have another remote Mysql database which resides in a Windows machine, with loads of data.Now, I have to connect to the remote Mysql database to pull data and populate them into my Sqlite database with the help of sqlAlchemy.
What I had been doing: I used mysql workbench to query data from the mysql database, export results to a csv file, load the csv file into my pyramid initializedb.py through python's default csv module, and then finally insert the retrieved rows into my Sqlite database.
What I want to do: I want to connect to the remote Mysql database from my initializedb.py itself, fetch results and insert them into my sqlite database.
How do I go on about with this? Any help is appreciated.

You can create a connection into your mysql db within the initializedb.py, extract the data and store them into your local db. Now, you will find the basics about sqlalchemy here:
http://docs.sqlalchemy.org/en/rel_0_9/core/tutorial.html
If you need this configurable, then you can put the url of your database into your config and access it through settings.
Also, you do not have to define the structure of your tables exactly, you can use something like:
users = Table('users', metadata, autoload=True)
On the other hand, if your MySQL db structure is the same as the sqlite db structure, it might be possible to reuse your model, but that would probably be hard to explain here without seeing any of your code.

TSQL with SQLAlchemy does not execute

I'm trying to execute TSQL queries in a remote MSSQL database by using SQLAlchemy and pymssql. I've tested my procedural query directly in the database and it works as intended, it also works if I run it directly through pymssql. If I run a regular one liner queries such as:
select table_name from INFORMATION_SCHEMA.tables
Through SQLAlchemy this also works as it should. But when I try to execute the following TSQL query it does not actually create the table:
IF NOT EXISTS (SELECT *
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = 'SOME_TABLE')
BEGIN
CREATE TABLE SOME_TABLE (SOME_TEXT VARCHAR(255), SOME_TIME DATETIME)
END
it runs it as it was successful and if I try to read the result it from the execution it gives me "Resource already closed error" as expected since it is a CREATE query. However if I try to add data to table 'SOME_TABLE' it pukes at me and says that the table does not exist. Feels like it is only uploading the query as a function but never executes it. Any ideas? Or even better; TSQL queries that actually works when executing with SQLAlchemy and pymssql.
Thanks,

You need to commit your pending changes in the Session. For basic understanding of the process read Using the Session. Quick solution:
session.commit()

TIME and TEXT are reserve words.
I do not know how SQL Alchemy or pymmsql talks to SQL Server. Either native client or ODBC. It eventually all boils down to a tabular data stream (TDS) over a network protocol like TCP/IP.
Check out the reserve word list on TECHNET.
-- Create table ?
IF OBJECT_ID('DBO.SOMETABLE') IS NULL
CREATE TABLE DBO.SOMETABLE (MY_TEXT VARCHAR(255), MY_TIME DATETIME);
I use the OBJECT_ID function since it is less typing.
But NOT EXITS works with both SELECT FROM the sys.objects or information_schema.tables with correct WHERE clauses.

PyMysql UPDATE query

I've been trying using PyMysql and so far everything i did worked (Select/insert) but when i try to update it just doesn't work, no errors no nothing, just doesn't do anything.
import pymysql
connection = pymysql.connect(...)
cursor = connection.cursor()
cursor.execute("UPDATE Users SET IsConnected='1' WHERE Username='test'")
cursor.close()
connection.close()
and yes I've double checked that Users, IsConnected and Username are all correct and test does exist (SELECT works on it)
what's my problem here?

When you execute your update, MySQL is implicitly starting a transaction. You need to commit this transaction by calling connection.commit() after you execute your update to keep the transaction from automatically rolling back when you disconnect.
MySQL (at least when using the InnoDB engine for tables) supports transactions, which allow you to run a series of update/insert statements then have them either all commit at once effectively as a single operation, or rollback so that none are applied. If you do not explicitly commit a transaction, it will rollback automatically when you close your connection to the database.

In fact, what #JoeDay has described above has little to do with default MySQL transaction's behaviour. MySQL by default operates in auto-commit mode and normally you don't need any additional twist to persist your changes:
By default, MySQL runs with autocommit mode enabled. This means that as soon as you execute a statement that updates (modifies) a table, MySQL stores the update on disk to make it permanent. The change cannot be rolled back.
PEP-249's (DB API) authors decided to complicate things and break Zen of Python by making a transaction's start implicit, by proposing auto-commit to be disabled by default.
What I suggest to do, is to restore MySQL's default behaviour. And use transactions explicitly, only when you need them.
import pymysql
connection = pymysql.connect(autocommit=True)
I've also written about it here with a few references.

sqlite3.OperationalError: database is locked

I'm trying to insert all values of a list to my sqlite3 database. When I simulate this query by using the python interactive interpreter, I am able to insert the single value to DB properly. But my code fails while using an iteration:
...
connection=lite.connect(db_name)
cursor=connection.cursor()
for name in match:
cursor.execute("""INSERT INTO video_dizi(name) VALUES (?)""",(name,))
connection.commit()
...
error:cursor.execute("""INSERT INTO video_dizi(name) VALUES (?)""",(name,))
sqlite3.OperationalError: database is locked
Any way to overcome this problem?

Do you have another connection elsewhere in your code that you use to begin a transaction that is still active (not committed) when you try to commit the operation that fails?

As this error can happen because you have opened your site.db or database file in DBbrowser type application to view in interactive database interface. Just close that it will work fine.

Because your database is use by another process or connection. If you need real concurrency, use a real RDBMS.