Normally, when trying to connect to a SQL sever DB in Python, I use the pyodbc package like this:
import pyodbc
conn = pyodbc.connect("Driver={SQL Server};"
"Server=<server-ip>;"
"Database=<DB-name>;"
"UID=<user-name>;"
"PWD=<password>;"
"Trusted_Connection=yes;"
)
However, I don't know how to connect to a linked server in Python. If my linked server is called linked-server and has a DB called linked-DB for example; I have tried the same connection string as above, and changing the database name like this: "Database=<linked-server>.<linked-DB>;", since that's how I query the linked server DB in SSMS. But this doesn't work in Python.
Thank you very much for your help.
Related
I wrote a Python program that web scraped a website and added the results to a Microsoft Access database. I now want to run the script again, with it adding the data to an Azure SQL database. I keep getting this error.
A network-related or instance-specific error has occurred while establishing a connection to SQL Server. Server is not found or not accessible. Check if instance name is correct and if SQL Server is configured to allow remote connections.
I have tried t edit the settings of the database to no avail. Could someone tell me what settings to apply to the database? I also tried to see if there was a way to run the Python script inside azure to try to avoid the problem. Is this possible?
cnxn = pyodbc.connect(r'Driver={ODBC Driver 18 for SQL Server};Server=tcp:servername.database.windows.net,1433;Database=sizedb3;Uid={your_user_name};Pwd={your_password_here};Encrypt=yes;TrustServerCertificate=no;Connection Timeout=30;Authentication=ActiveDirectoryPassword')
I tried this driver. I have downloaded the driver from Microsoft's website. This driver is a connection string in the ODBC section of the Azure SQL database in the Azure portal.
I tried running the below python code to connect to Azure SQL DB with Azure AD authentication.
Code:-
import pyodbc
conn = pyodbc.connect('Driver={ODBC Driver 17 for SQL Server};'
'Server=tcp:siliconserver.database.windows.net,1433;'
'Database=silicondb;'
'Uid=xxxser#sid24desaioutlook.onmicrosoft.com;'
'Pwd=xxxxxxxxxx#123;'
'authentication=ActiveDirectoryPassword')
cursor = conn.cursor()
cursor.execute('SELECT * FROM StudentReviews')
for i in cursor:
print(i)
cursor.close()
conn.close()
Output:-
Make sure you have allowed your Client IP in your Azure SQL server Networking tab like below:-
I tried to remove one syntax/spelling from my Azure SQL connection string and got the same error code as yours like below:-
You can validate your connection string server spelling and syntax from your Azure SQL server DB > Connection String > like below:-
Also, Make sure you have added your client IP and allowed it in your Azure SQL Server like below:-
So I am trying to communicate to a Google Cloud SQL Server that I have created with an external python program that I have written in VS Code but I don't know where to begin. Any help will be useful.
I'd recommend using the Cloud SQL Python Connector to manage your connections to Cloud SQL. It supports the pytds driver and should help resolve your troubles for connecting to a SQL Server instance from a Python application.
from google.cloud.sql.connector import connector
import sqlalchemy
# configure Cloud SQL Python Connector properties
def getconn() ->:
conn = connector.connect(
"PROJECT:REGION:INSTANCE",
"pytds",
user="YOUR_USER",
password="YOUR_PASSWORD",
db="YOUR_DB"
)
return conn
# create connection pool to re-use connections
pool = sqlalchemy.create_engine(
"mssql+pytds://localhost",
creator=getconn,
)
# query or insert into Cloud SQL database
with pool.connect() as db_conn:
# query database
result = db_conn.execute("SELECT * from my_table").fetchall()
# Do something with the results
for row in result:
print(row)
For more detailed examples and additional params refer to the README of the repository.
I think you can be inspired by this :Python django
"Run the app on your local computer"
I am attempting to create a flask web application that uses mysql to store users and some other data. When I use the following code
import MySQLdb
def connection():
conn = MySQLdb.connect(host='localhost', user='root', passwd='password', database='data')
c = conn.cursor()
return c, conn
I get a 500 internal service error. This code will connect on the command line, and my flask site works fine until I add the line
from dbconnect import connection
I have tried using different ways to connect to the database, (python connector, pymysql). They all give the same error. I have also tried updating permissions from inside mysql to the user. I have been following tutorials from https://pythonprogramming.net/flask-connect-mysql-using-mysqldb-tutorial/ but they did not get these errors in the tutorial and I have followed most of the tutorial exactly.
I have a database that I am running on my local machine which I can access through Microsoft SQL Server Manager Studio. I connect to this server "JIMS-LAPTOP\SQLEXPRESS" and then I can run queries through the manager. However I need to be able to connect to this database and work with it through python.
When I try to connect using sqlite3 like
conn = sqlite3.connect("JIMS-LAPTOP\SQLEXPRESS")
I get an unable to open database file error
I tried accessing the temporary file directly like this
conn = sqlite3.connect("C:\Users\Jim Notaro\AppData\Local\Temp\~vs13A7.sql")
c = conn.cursor()
c.execute("SELECT name FROM sqlite_master WHERE type = \"table\"")
print c.fetchall()
Which allows me to access a database but it is completely empty (No tables are displayed)
I also tried connecting like this
conn = sqlite3.connect("SQL SERVER (SQLEXPRESS)")
Which is what the name is in the sql server configuration manager but that also returns a blank database.
I'm not sure how I am suppose to be connecting to the database using python
You can't use sqlite3 to connect to SQL server, only to Sqlite databases.
You need to use a driver that can talk to MS SQL, like pyodbc.
I'm trying to connect to a SQL Server 2012 database using SQLAlchemy (with pyodbc) on Python 3.3 (Windows 7-64-bit). I am able to connect using straight pyodbc but have been unsuccessful at connecting using SQLAlchemy. I have dsn file setup for the database access.
I successfully connect using straight pyodbc like this:
con = pyodbc.connect('FILEDSN=c:\\users\\me\\mydbserver.dsn')
For sqlalchemy I have tried:
import sqlalchemy as sa
engine = sa.create_engine('mssql+pyodbc://c/users/me/mydbserver.dsn/mydbname')
The create_engine method doesn't actually set up the connection and succeeds, but
iIf I try something that causes sqlalchemy to actually setup the connection (like engine.table_names()), it takes a while but then returns this error:
DBAPIError: (Error) ('08001', '[08001] [Microsoft][ODBC SQL Server Driver][DBNETLIB]SQL Server does not exist or access denied. (17) (SQLDriverConnect)') None None
I'm not sure where thing are going wrong are how to see what connection string is actually being passed to pyodbc by sqlalchemy. I have successfully using the same sqlalchemy classes with SQLite and MySQL.
The file-based DSN string is being interpreted by SQLAlchemy as server name = c, database name = users.
I prefer connecting without using DSNs, it's one less configuration task to deal with during code migrations.
This syntax works using Windows Authentication:
engine = sa.create_engine('mssql+pyodbc://server/database')
Or with SQL Authentication:
engine = sa.create_engine('mssql+pyodbc://user:password#server/database')
SQLAlchemy has a thorough explanation of the different connection string options here.
In Python 3 you can use function quote_plus from module urllib.parse to create parameters for connection:
import urllib
params = urllib.parse.quote_plus("DRIVER={SQL Server Native Client 11.0};"
"SERVER=dagger;"
"DATABASE=test;"
"UID=user;"
"PWD=password")
engine = sa.create_engine("mssql+pyodbc:///?odbc_connect={}".format(params))
In order to use Windows Authentication, you want to use Trusted_Connection as parameter:
params = urllib.parse.quote_plus("DRIVER={SQL Server Native Client 11.0};"
"SERVER=dagger;"
"DATABASE=test;"
"Trusted_Connection=yes")
In Python 2 you should use function quote_plus from library urllib instead:
params = urllib.quote_plus("DRIVER={SQL Server Native Client 11.0};"
"SERVER=dagger;"
"DATABASE=test;"
"UID=user;"
"PWD=password")
I have an update info about the connection to MSSQL Server without using DSNs and using Windows Authentication. In my example I have next options:
My local server name is "(localdb)\ProjectsV12". Local server name I see from database properties (I am using Windows 10 / Visual Studio 2015).
My db name is "MainTest1"
engine = create_engine('mssql+pyodbc://(localdb)\ProjectsV12/MainTest1?driver=SQL+Server+Native+Client+11.0', echo=True)
It is needed to specify driver in connection.
You may find your client version in:
control panel>Systems and Security>Administrative Tools.>ODBC Data
Sources>System DSN tab>Add
Look on SQL Native client version from the list.
Just want to add some latest information here:
If you are connecting using DSN connections:
engine = create_engine("mssql+pyodbc://USERNAME:PASSWORD#SOME_DSN")
If you are connecting using Hostname connections:
engine = create_engine("mssql+pyodbc://USERNAME:PASSWORD#HOST_IP:PORT/DATABASENAME?driver=SQL+Server+Native+Client+11.0")
For more details, please refer to the "Official Document"
import pyodbc
import sqlalchemy as sa
engine = sa.create_engine('mssql+pyodbc://ServerName/DatabaseName?driver=SQL+Server+Native+Client+11.0',echo = True)
This works with Windows Authentication.
I did different and worked like a charm.
First you import the library:
import pandas as pd
from sqlalchemy import create_engine
import pyodbc
Create a function to create the engine
def mssql_engine(user = os.getenv('user'), password = os.getenv('password')
,host = os.getenv('SERVER_ADDRESS'),db = os.getenv('DATABASE')):
engine = create_engine(f'mssql+pyodbc://{user}:{password}#{host}/{db}?driver=SQL+Server')
return engine
Create a variable with your query
query = 'SELECT * FROM [Orders]'
Execute the Pandas command to create a Dataframe from a MSSQL Table
df = pd.read_sql(query, mssql_engine())