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run python file from different directory including sqlite database

This code runs perfectly fine if I first redirect to the folder where this main.py file is located. So in cmd I just type: python main.py. In this folder is also my database "Datalog.db" located.
If I run this python file from somewhere else, I get a problem with this line of code: cur.execute(sql). So in cmd I type: python C:\Users\ [...] \main.py. I get following error: "sqlite3.OperationalError: no such table: Datalog". Later I want to include this python file in a pythonshell in node-red and there I have to define the full path of this main.py
I also tried to build an exe-file with it but then the same error occurs:"sqlite3.OperationalError: no such table: Datalog".
Apparently the connection to the database is not the issue, first my cur.execute command is not working.
I find out that I have to "include my SQLite database file in the include_files statement", but I have no idea how to do this ..
Can anybody help? I am very sorry for any inconvenience, I just started programming and this is my first post.
import sqlite3 as db
db_name = 'Datalog'
output_number = 'Output1'
output = 'hello'
timestamp = '2019-11-11 09:27:02'
db_name = f'{db_name}.db'
con = db.connect(db_name)
with con:
cur = con.cursor()
sql = f"UPDATE Datalog SET {output_number}='{output}' WHERE timestamp ='{timestamp}'"
cur.execute(sql)
con.commit()
print("### DB updated ###")

You can change db_name to the full path of your sqlite database or even better, dynamically build the path to the db (Below code assumes the db is in the same folder (directory) as the file which calls the below code ):
import os.path
db_name = os.path.dirname(os.path.abspath(__filename__)) + 'Datalog'

python looks for files in "sys.path" so you want to insert the name of the directory containing your file in that path so python can find it
here is an example:
import sys
sys.path.insert(0, r'C:\Users\Philip\Work\Bin')
where 0 is the position in the sys.path, 0 means top, 1 means second from top etc.
obviously you would replace my directory with yours

Export data from Oracle Database 12c using Python 2.7

I'm trying to export a table, contained within an Oracle 12c database, to csv format - using Python 2.7. The code I have written is shown below:
import os
import cx_Oracle
import csv
SQL = 'SELECT * FROM ORACLE_TABLE'
filename = 'C:\Temp\Python\Output.csv'
file = open(filename, 'w')
output = csv.writer(file, dialect='excel')
connection = cx_Oracle.connect('username/password#connection_name')
cursor = connection.cursor()
cursor.execute(SQL)
for i in cursor:
output.writerow(i)
cursor.close()
connection.close()
file.close()
This code yields an error in the line where I define 'connection':
ORA-12557: TNS:protocol adapter not loadable
How can I remedy this? Any help would be appreciated.
Please note: I have already encountered StackOverflow responses to very similar problems to this. However, they often suggest changing the path within environment variables - I cannot do this since I don't have appropriate administer privileges. Thanks again for your assistance.

ORA-12557 is caused by problems with the %ORACLE_HOME% on Windows. That's the usual suggestion is to change the PATH setting.
"I cannot do this since I don't have appropriate administer privileges."
In which case you don't have too many options. Perhaps you could navigate to the ORACLE_HOME directory and run your script from there. Otherwise look to see what other tools you have available: Oracle SQL Developer? TOAD? SQL*Plus?

We found that by navigating to config -> Oracle and editing the file 'tnsnames.ora' the problem can be solved. The tnsnames file appears as follows:
connection_name =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS= ... )
)
(CONNECT_DATA =
(SERVICE_NAME= ...)
)
)
By changing the first instance of connection_name to connection_name.WORLD, then typing
set ORACLE_HOME=
into the command line before executing the Python script, the above script now runs with no error.

I use ini-file to store DB connection parameters. Hope it helps.
self.mydsn = cx_Oracle.makedsn(self.parser.get('oracle', 'db'),self.parser.get('oracle', 'port'),self.parser.get('oracle', 'service_name'))
try:
self.connpool = cx_Oracle.SessionPool(user=self.parser.get('oracle', 'username'),password=self.parser.get('oracle', 'userpass'),dsn=self.mydsn,min=1,max=5,increment=1)
except Exception as e:
print e

You can use this python script for oracle csv export:
https://github.com/teopost/csv_exp

comparing a given variable to data in a database and checking to see if it exists

I have a sqlite db of API keys and I want to make something check and see if the given key is in the database.I'm generating the API keys using another python script named apikeygen.py. I'm using python 2.7 and pattern 2.6. This is going to be a data scraping/mining/filtering application that I'm doing just for fun and maybe have a future use for malware analysis.
I need help getting the main piece of code that we will call API.py to check and see if the given API key is in the database.
This is the code for the API.py file so far.
import os, sys; sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", ".."))
import sqlite3 as lite
from pattern.server import App
from pattern.server import MINUTE, HOUR, DAY
app = App("api")
def search_db(key=''):
con = lite.connect('apikeys.db')
with con:
cur = con.cursor()
cur.execute("SELECT * FROM keys")
while True:
row = cur.fetchone()
if row == None:
break
print row[2]

I'm still not really clear what you are asking. Why don't you explicitly query for the key, rather than iterating over your whole table?
cur.execute("SELECT * FROM keys WHERE key = ?", (key,))

using python 2.7 to query sqlite3 database and getting "sqlite3 operational error no such table"

My simple test code is listed below. I created the table already and can query it using the SQLite Manager add-in on Firefox so I know the table and data exist. When I run the query in python (and using the python shell) I get the no such table error
def TroyTest(self, acctno):
conn = sqlite3.connect('TroyData.db')
curs = conn.cursor()
v1 = curs.execute('''
SELECT acctvalue
FROM balancedata
WHERE acctno = ? ''', acctno)
print v1
conn.close()

When you pass SQLite a non-existing path, it'll happily open a new database for you, instead of telling you that the file did not exist before. When you do that, it'll be empty and you'll instead get a "No such table" error.
You are using a relative path to the database, meaning it'll try to open the database in the current directory, and that is probably not where you think it is..
The remedy is to use an absolute path instead:
conn = sqlite3.connect('/full/path/to/TroyData.db')
You need to loop over the cursor to see results:
curs.execute('''
SELECT acctvalue
FROM balancedata
WHERE acctno = ? ''', acctno)
for row in curs:
print row[0]
or call fetchone():
print curs.fetchone() # prints whole row tuple

The problem is the SQL statment. you must specify the db name and after the table name...
'''SELECT * FROM db_name.table_name WHERE acctno = ? '''

pyodbc path in sql statement not working

I`m quite new to python and would like to copy a table from one mdb to another mdb using pyodbc. There seems to be a problem with the paths if a Foldername starts with a digit. I googled for an hour now and couldn't find a solution:
DBfile = r"W:\path\1020 Folder\MDB1.mdb"
conn = pyodbc.connect('DRIVER={Microsoft Access Driver (*.mdb)};DBQ='+DBfile1)
cursor = conn.cursor()
sql = """SELECT Table1.* INTO test FROM [W:\path\A 1020 Folder\MB2.mdb].Table1;"""
sql1 = """SELECT Table1.* INTO test FROM [W:\path\1020 Folder\MB2.mdb].Table1;"""
cursor.execute(sql) #WORKING
cursor.execute(sql1) #NOT WORKING
conn.commit()
Thanks alot, Achim

You must be very careful when you want to use backshlash \ in strings. You can escape those using \\:
sql1 = """SELECT Table1.* INTO test FROM [W:\\path\\1020 Folder\\MB2.mdb].Table1;"""
You can also use raw string just like you did it with DBfile