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How to connect with oracle database?

I am using this code to connect with oracle database:
import cx_Oracle
conn_str = u"jbdc:oracle:thin:#****_***.**.com"
conn = cx_Oracle.connect(conn_str)
c = conn.cursor()
However, I am getting this error:
ORA-12560: TNS:protocol adapter error
How can I resolve it?
Thank you

You cannot use a JDBC thin connect string to connect with cx_Oracle (or the new python-oracledb). You must use either an alias found in a tnsnames.ora file, or the full connect descriptor (such as that found in a tnsnames.ora) file or an EZ+ Connect string. An example follows:
conn_str = "user/password#host:port/service_name"
With the new python-oracledb driver you can also do this:
import oracledb
conn = oracledb.connect(user="USER", password="PASSWORD", host="my_host",
port=1521, service_name="my_service")
See the documentation for more details.

Getting Login Failed error with sqlalchemy+PYODBC when trying to connect to mssql DB server with another Domain credentials,but connected with Pymssql [duplicate]

I am trying to use Python to connect to a SQL database by using Window authentication. I looked at some of the posts here (e.g., here), but the suggested methods didn't seem to work.
For example, I used the following code:
cnxn = pyodbc.connect(driver='{SQL Server Native Client 11.0}',
server='SERVERNAME',
database='DATABASENAME',
trusted_connection='yes')
But I got the following error:
Error: ('28000', "[28000] [Microsoft][SQL Server Native Client 11.0][SQL Server]
Login failed for user 'DOMAIN\\username'. (18456) (SQLDriverConnect); [28000] [Microsoft]
[SQL Server Native Client 11.0][SQL Server]Login failed for user 'DOMAIN\\username'.
(18456)")
(Note that I replaced the actual domain name and user name with DOMAIN and username respectively, in the error message above.)
I also tried using my UID and PWD, which led to the same error.
Lastly, I tried to change the service account by following the suggestion from the link above, but on my computer, there was no Log On tab when I went to the Properties of services.msc.
I wonder what I did wrong and how I can fix the problem.

Connecting from a Windows machine:
With Microsoft's ODBC drivers for SQL Server, Trusted_connection=yes tells the driver to use "Windows Authentication" and your script will attempt to log in to the SQL Server using the Windows credentials of the user running the script. UID and PWD cannot be used to supply alternative Windows credentials in the connection string, so if you need to connect as some other Windows user you will need to use Windows' RUNAS command to run the Python script as that other user..
If you want to use "SQL Server Authentication" with a specific SQL Server login specified by UID and PWD then use Trusted_connection=no.
Connecting from a non-Windows machine:
If you need to connect from a non-Windows machine and the SQL Server is configured to only use "Windows authentication" then Microsoft's ODBC drivers for SQL Server will require you to use Kerberos. Alternatively, you can use FreeTDS ODBC, specifying UID, PWD, and DOMAIN in the connection string, provided that the SQL Server instance is configured to support the older NTLM authentication protocol.

I tried everything and this is what eventually worked for me:
import pyodbc
driver= '{SQL Server Native Client 11.0}'
cnxn = pyodbc.connect(
Trusted_Connection='Yes',
Driver='{ODBC Driver 11 for SQL Server}',
Server='MyServer,1433',
Database='MyDB'
)

Try this cxn string:
cnxn = pyodbc.connect('DRIVER={SQL Server};SERVER=localhost;PORT=1433;DATABASE=testdb;UID=me;PWD=pass')
http://mkleehammer.github.io/pyodbc/

I had similar issue while connecting to the default database (MSSQLSERVER). If you are connecting to the default database, please remove the
database='DATABASENAME',
line from the connection parameters section and retry.
Cheers,
Deepak

The first option works if your credentials have been stored using the command prompt. The other option is giving the credentials (UId, Psw) in the connection.
The following worked for me:
conn = pyodbc.connect('DRIVER={SQL Server};SERVER=yourServer;DATABASE=yourDatabase;UID=yourUsername;PWD=yourPassword')

import pyodbc #For python3 MSSQL
cnxn = pyodbc.connect("Driver={SQL Server};" #For Connection
"Server=192.168.0.***;"
"PORT=1433;"
"Database=***********;"
"UID=****;"
"PWD=********;")
cursor = cnxn.cursor() #Cursor Establishment
cursor.execute('select site_id from tableName') #Execute Query
rs = cursor.fetchall()
print(rs)

A slightly different use case than the OP, but for those interested it is possible to connect to a MS SQL Server database using Windows Authentication for a different user account than the one logged in.
This can be achieved using the python jaydebeapi module with the JDBC JTDS driver. See my answer here for details.

Note that you may need to change the authentication mechanism. For example, my database is using ADP. So my connection looks like this
pyodbc.connect(
Trusted_Connection='No',
Authentication='ActiveDirectoryPassword',
UID=username,
PWD=password,
Driver=driver,
Server=server,
Database=database)
Read more here

Trusted_connection=no did not helped me. When i removed entire line and added UID, PWD parameter it worked. My takeaway from this is remove

Connect to HANA from Python

I am trying to connect to HANA in order to pull some metadata in a pandas dataframe. There are lots of mixed approaches and I couldn't find anything concrete.
All I have is:
username
password
serverip
servername
and table names.
The admin has provided all the read access to the required account for the specific tables.
What is the quickest way to get this done? I do not have the option of installing anything on SAPs site.
I have tried the below snippets but I get the error 'target machine actively refused it' and to debug at SAPs end is a lost cause. Thank you in advance.
import pyhdb
connection = pyhdb.connect(
host="123.com",
port=123,
user="user",
password="pswrd"
)
cursor = connection.cursor()
cursor.execute("SELECT * FROM Tablename")
cursor.fetchone()
connection.close()
and
from hdbcli import dbapi
conn = dbapi.connect(
address="123.com",
port=123,
user="user",
password="pswrd"
)
cursor = conn.cursor()

Given your server address and port examples, I'm not sure you got the right idea for how to connect to a HANA database.
Since you want to use pandas it is probably a good idea to have a look at the SAP HANA Machine Learning library for Python.
Check the tutorial blog post for this:
https://blogs.sap.com/2019/11/05/hands-on-tutorial-machine-learning-push-down-to-sap-hana-with-python/
To do any of this, there is no need to install or debug anything on the HANA system.

To connect to hana DB :
from hdbcli import dbapi
conn = dbapi.connect(
address="serverhost",
port=39015,
user="UserName",
password="Password",
databasename='DBNAME'
)
Make sure you enter the correct port number
To get the sql results in pandas dataframe:
query = 'select * from table'
df = pd.read_sql_query(query, conn)
df.head()

Need help in fixing sql connection issue using service account though pyodbc

When I try to run the below code I am getting following error. Tried referring other posts but it does not seem to help.
The server principal "{Myuser}" is not able to access the database "{database}" under the current security context. (916) (SQLExecDirectW)'
import pyodbc
cnxn = pyodbc.connect("Driver={SQL Server};"
'Server=XXXXXXX;'
'Port=xxxx'
'Username={service_account}'
'Password={password of service_account}'
'Database={detabase};'
'Trusted_Connection=yes;')
results = cnxn.cursor()
results.execute('SELECT * FROM {database}.dbo.{tablename}')
for row in results:
print(row)

If you are going to use Microsoft's ODBC driver for SQL Server and Trusted_Connection=yes (SQL Server Windows authentication) then you don't pass the Windows credentials in the connection string. Instead, you run your Python app as the Windows user. Ways to do that include
launching the Python app from a Windows command prompt using the RUNAS command, or
Shiftright_clicking your app's icon, then choose "Run as different user".
Another option might be to use the FreeTDS ODBC driver. It supports the older NTLM authentication protocol and allows you to specify the DOMAIN, UID, and PWD (for Windows authentication) in the connection string.

This worked for me:
import pyodbc
password = "<password>"
conn = pyodbc.connect("Driver={SQL Server};Server=<host>;Port=<port>;UID=
<username>;PWD=" + password + ";Database=<dbname>;")
cursor = conn.cursor()
cursor.execute('SELECT * FROM <table>')
for row in cursor:
print(row)

SQL Server connection - Works in pyodbc, but not SQLAlchemy

This is a fairly common question but even using the answers on SO like here but I still can't connect.
When I setup my connection to pyodbc I can connect with the following:
cnxn = pyodbc.connect('DRIVER={SQL Server Native Client 11.0};SERVER=ip,port;DATABASE=db;UID=user;PWD=pass')
cursor = cnxn.cursor()
cursor.execute("some select query")
for row in cursor.fetchall():
print(row)
and it works.
However to do a .read_sql() in pandas I need to connect with sqlalchemy.
I have tried with both hosted connections and pass-through pyodbc connections like the below:
quoted = urllib.parse.quote_plus('DRIVER={SQL Server Native Client 11.0};Server=ip;Database=db;UID=user;PWD=pass;Port=port;')
engine = sqlalchemy.create_engine('mssql+pyodbc:///?odbc_connect={}'.format(quoted))
engine.connect()
I have tried with both SERVER=ip,port format and the separate Port=port parameter like above but still no luck.
The error I'm getting is Login failed for user 'user'. (18456)
Any help is much appreciated.

I assume that you want to create a DataFrame so when you have a cnxn you can pass it to Pandas read_sql_query function.
Example:
cnxn = pyodbc.connect('your connection string')
query = 'some query'
df = pandas.read_sql_query(query, conn)