Using Oracle Service Names with SQLAlchemy

The module sqlalchemy now can handle oracle service_names. Have a look:

from sqlalchemy.engine import create_engine

DIALECT = 'oracle'
SQL_DRIVER = 'cx_oracle'
USERNAME = 'your_username' #enter your username
PASSWORD = 'your_password' #enter your password
HOST = 'subdomain.domain.tld' #enter the oracle db host url
PORT = 1521 # enter the oracle port number
SERVICE = 'your_oracle_service_name' # enter the oracle db service name
ENGINE_PATH_WIN_AUTH = DIALECT + '+' + SQL_DRIVER + '://' + USERNAME + ':' + PASSWORD +'@' + HOST + ':' + str(PORT) + '/?service_name=' + SERVICE

engine = create_engine(ENGINE_PATH_WIN_AUTH)


#test query
import pandas as pd
test_df = pd.read_sql_query('SELECT * FROM global_name', engine)

I've found the answer you have to use the same connection string that would be used in a tnsnames.ora file in the connection string after the '@" like so

from sqlalchemy import create_engine

if __name__ == "__main__":                                                                                                                                                        
    engine = create_engine("oracle+cx_oracle://<username>:<password>@(DESCRIPTION = (LOAD_BALANCE=on) (FAILOVER=ON) (ADDRESS = (PROTOCOL = TCP)(HOST = <host>)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = devdb)))")                                                                                                                                                   
    result = engine.execute("create table test_table (id NUMBER(6), name VARCHAR2(15) not NULL)")
    result = engine.execute("drop table test_table")

This example runs just fine, and you can comment out the drop statement and check the DB to see that the table was created.

import cx_Oracle
dsnStr = cx_Oracle.makedsn('myhost','port','MYSERVICENAME')
connect_str = 'oracle://user:password@' + dsnStr.replace('SID', 'SERVICE_NAME')

The makedns will create a TNS like this:

(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=myhost)(PORT=1530)))(CONNECT_DATA=(SID=MYSERVICENAME)))

replacing "SID" with "SERVICE_TYPE" got it to work for me.

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If you are using flask, sqlalchemy, and oracle:

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
import cx_Oracle

app = Flask(__name__)
dnsStr = cx_Oracle.makedsn('my.host.com', '1530', 'my.service.name')
dnsStr = dnsString.replace('SID', 'SERVICE_NAME')
app.config['SQLALCHEMY_DATABASE_URI'] = 'oracle://myschema:mypassword@' + dnsStr
db = SQLAlchemy(app)