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Connect to mssql from python

I am trying to connect mssql from python. For this I am using below code but looks like something is wrong with the connection. Can anyone help me ?
import sqlalchemy as sal
from sqlalchemy import create_engine
import pyodbc
##conn = pyodbc.connect('Driver={SQL Server Native client 11.0};server=localhost;database=Nifty;trusted_connection=yes;')
engine = sal.create_engine('mssql+pyodbc://localhost/Nifty?driver=SQL+Server+Native+client+11.0?Trusted_Connection=yes')
engine.execute('select top 2 * from [dbo].ABC')
I am getting below error
InterfaceError: (pyodbc.InterfaceError) ('IM002', '[IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified (0) (SQLDriverConnect)')
(Background on this error at: https://sqlalche.me/e/14/rvf5)

pls first check if you have specified driver in connection:
control panel>Systems and Security>Administrative Tools.>ODBC Data Sources>System DSN tab>Add
and then try :
engine = sal.create_engine('mssql+pyodbc://localhost/Nifty?driver=SQL+Server+Native+client+11.0?Trusted_Connection=yes',echo = True)
official docs
or, You can use some of the Solutions below:
Solution 1
define driver like this :
Driver={ODBC Driver 17 for SQL Server};Server=serverName\instanceName;Database=myDataBase;Trusted_Connection=yes;
and then put it in pyodbc.connect(" here ") and run it using cursor, see this
Solution 2
With Windows Authentication Without using DSN's
engine = sal.create_engine('mssql+pyodbc://server/db')
Solution 3
using urllib
import urllib
params = urllib.parse.quote_plus("DRIVER={SQL Server Native Client 11.0};"
"SERVER=dagger;"
"DATABASE=test;"
"Trusted_Connection=yes")
engine = sa.create_engine("mssql+pyodbc:///?odbc_connect={}".format(params))

How to do df.to_sql using SQL Server in Azure

I can do a df.to_slq on my local instance of SQL Server just fine. I am getting stuck when trying to do the same df.to_sll using Python and Azure SQL Server. I thought it would essentially be done like this.
import urllib.parse
params = urllib.parse.quote_plus(
'Driver=%s;' % '{ODBC Driver 17 for SQL Server}' +
'Server=%s,1433;' % 'ryan-server.database.windows.net' +
'Database=%s;' % 'ryan_sql_db' +
'Uid=%s;' % 'UN' +
'Pwd={%s};' % 'PW' +
'Encrypt=no;' +
'TrustServerCertificate=no;'
)
from sqlalchemy.engine import create_engine
conn_str = 'mssql+pyodbc:///?odbc_connect=' + params
engine = create_engine(conn_str)
connection = engine.connect()
connection
all_data.to_sql('health', engine, if_exists='append', chunksize=100000, method=None,index=False)
That is giving me this error.
OperationalError: (pyodbc.OperationalError) ('08S01', '[08S01] [Microsoft][ODBC Driver 17 for SQL Server]TCP Provider: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.\r\n (10060) (SQLExecDirectW); [08S01] [Microsoft][ODBC Driver 17 for SQL Server]Communication link failure (10060)')
[SQL: INSERT INTO health ([0], [Facility_BU_ID], [Code_Type], [Code], [Description], [UB_Revenue_Code], [UB_Revenue_Description], [Gross_Charge], [Cash_Charge], [Min_Negotiated_Rate], [Max_Negotiated_Rate], etc., etc., etc.
I found this link today:
https://learn.microsoft.com/en-us/sql/machine-learning/data-exploration/python-dataframe-sql-server?view=sql-server-ver15
I tried to do something similar, like this.
import pyodbc
import pandas as pd
df = all_data
# server = 'myserver,port' # to specify an alternate port
server = 'ryan-server.database.windows.net'
database = 'ryan_sql_db'
username = 'UN'
password = 'PW'
cnxn = pyodbc.connect('DRIVER={SQL Server};SERVER='+server+';DATABASE='+database+';UID='+username+';PWD='+ password)
cursor = cnxn.cursor()
# Insert Dataframe into SQL Server:
for index, row in df.iterrows():
cursor.execute(all_data.to_sql('health', cnxn, if_exists='append', chunksize=100000, method=None,index=False))
cnxn.commit()
cursor.close()
When I run that, I get this error.
DatabaseError: Execution failed on sql 'SELECT name FROM sqlite_master WHERE type='table' AND name=?;': ('42S02', "[42S02] [Microsoft][ODBC SQL Server Driver][SQL Server]Invalid object name 'sqlite_master'. (208) (SQLExecDirectW); [42S02] [Microsoft][ODBC SQL Server Driver][SQL Server]Statement(s) could not be prepared. (8180)")
What I'm really hoping to to is df.to_sql, not Insert Into. I am working in Spyder and trying to send the data from my local machine to the cloud.

I read the two links below, and got it working.
https://learn.microsoft.com/en-us/sql/relational-databases/system-stored-procedures/sp-set-database-firewall-rule-azure-sql-database?view=azuresqldb-current
https://www.virtual-dba.com/blog/firewalls-database-level-azure-sql/
Basically, you need to open your command window on your local machine, enter 'ipconfig', and grab two IP addresses. Then, enter those into SQL Server in Azure.
EXECUTE sp_set_database_firewall_rule
N'health',
'192.0.1.1',
'192.0.0.5';
Finally, run the small script below, in SQL Server, to confirm that the changes were made correctly.
USE [ryan_sql_db]
GO
SELECT * FROM sys.database_firewall_rules
ORDER BY modify_date DESC

Pandas sqlalchemy create_engine connection with SQL server windows authentication

I am trying to upload a Pandas DataFrame to SQL server table. From reading, the sqlalchemy to_sql method seems like a great option. However, I am not able to get the create_engine to make the connection.
I am able to connect to the database to retrieve data with Windows authentication. Here is the connection string I am using:
cnxn = pyodbc.connect("Driver={SQL Server Native Client 11.0};"
"Server={server_name};"
"Database={database_name};"
"Trusted_Connection=yes;")
I have tried several different ways to use my login information to connect, here is the most recent version:
engine = create_engine(
"mssql+pyodbc://{network_user_name}:{network_pw}#{server_name}//{database_name}"
)
engine.connect()
Here is the error I am getting:
InterfaceError: (pyodbc.InterfaceError) ('IM002', '[IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified (0) (SQLDriverConnect)')
(Background on this error at: http://sqlalche.me/e/rvf5)

If you are going to use Windows authentication then you simply omit the username/password part of the connection URI. This works fine for me:
connection_uri = (
"mssql+pyodbc://#192.168.0.179:49242/mydb?driver=ODBC+Driver+17+for+SQL+Server"
)
engine = sa.create_engine(connection_uri)

pyodbc connect to a Sybase database in Python

I am trying to connect to Sybase using pyodbc.
conn = pyodbc.connect('DRIVER=/usr/lib64/libodbc.so;SERVER=DBName;DATABASE=Test;UID=username;PWD=password')
When i execute the above I get the following error.
Error: ('IM002', '[IM002] [unixODBC][SAP][ODBC Driver Manager] Unable to load resource file (-620) (SQLDriverConnect)')
I can connect to sybase using sqsh so the username and password are correct. Any other suggestions?
I am using Ubuntu 16.04. Not sure if that makes a difference.

try this please
import pyodbc
connection_string = "Driver=SQL Anywhere 17;Server=demo17;UID=dba;PWD=sql;DBN=demo"
connection_object = pyodbc.connect(connection_string)
cursor = connection_object.cursor()
sql_string = "select 1"
result = cursor.execute(sql_string)
counter = result.fetchone()[0]
print(counter)
connection_object.close()

I was using the incorrect driver.
It is a custom driver so I can't share.

pyodbc connection error when trying to connect to DB on localhost

I have a local DB on my machine called 'Test' which contains a table called 'Tags'. I am able to access this DB and query from this table through SQL Server management studio 2008.
However, when using pyodbc I keep running into problems.
Using this:
conn = pyodbc.connect('DRIVER={SQL Server};SERVER=localhost:1433;DATABASE=Test')
yields the error:
pyodbc.Error: ('08001', '[08001] [Microsoft][ODBC SQL Server Driver][DBNETLIB]Invalid connection. (14) (SQLDriverConnectW); [01000] [Microsoft][ODBC SQL Server Driver][DBNETLIB]ConnectionOpen (Invalid Instance()). (14)')
(with or without specifying the port)
Trying an alternative connection string:
conn = pyodbc.connect('DRIVER={SQL Server};SERVER=localhost\Test,1433')
yields no error, but then:
cur = conn.cursor()
cur.execute("SELECT * FROM Tags")
yields the error:
pyodbc.ProgrammingError: ('42S02', "[42S02] [Microsoft][ODBC SQL Server Driver][SQL Server]Invalid object name 'Tags'. (208) (SQLExecDirectW)")
Why could this be?

I tried changing your query to
SELECT * FROM Test.dbo.Tags
and it worked.

I don't see any authentication attributes in your connection strings. Try this (I'm using Windows authentication):
conn = pyodbc.connect('Trusted_Connection=yes', driver = '{SQL Server}',
server = 'localhost', database = 'Test')
cursor = conn.cursor()
# assuming that Tags table is in dbo schema
cursor.execute("SELECT * FROM dbo.Tags")

For me, apart from maintaining the connection details (user, server, driver, correct table name etc.),
I took these steps:
Checked the ODBC version here (Windows 10) ->
(search for) ODBC ->
Select 32/64 bit version ->
Drivers ->
Verify that the ODBC driver version is present there. If it is not, use this link to download the relevant driver: here
Reference Link: here

conn = pyodbc.connect('DRIVER={SQL Server};SERVER=localhost:1433;DATABASE=Test')
This connection lack of instance name and the port shouldn't be writen like this.
my connection is this:
cn=pyodbc.connect('DRIVER={SQL Server};SERVER=localhost\SQLEXPRESS;PORT=1433;DATABASE=ybdb;UID=sa;PWD=*****')
enter image description here

Try replacing 'localhost' with either '(local)' or '.'. This solution fixed the problem for me.