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Connecting R to Oracle DB without admin

I need an R script that allows me to connect to an Oracle DB without having to install anything needing admin powers, and preferrably nothing at all apart from package downloads. In python the following code works, I believe because it uses the cx_Oracle module as a portable driver. What would be a good R alternative?
import pandas as pd
import sqlalchemy
import sys
host = "xxx.intra"
database = "mydb"
user = "usr"
password = "pw"
def get_oracle_engine(host, database, user, password):
return sqlalchemy.create_engine("oracle+cx_oracle://{user}:{password}#{host}:1521/?service_name={database}".format(host=host, database=database, user=user, password=password))
engine=get_oracle_engine(host, database, user, password)
pd.read_sql_table("mytable", engine, schema= mydb,index.cols="id1")
I managed to install ROracle using the CRAN instructions but I keep getting the ORA-12154 TNS: cound not resolve the connect identifier specified when using:
library(ROracle)
con= DBI::dbconnect(dbDriver("Oracle"), user= user, password=password, host=host, dbname=database, port="1521")
By the way dbDriver("Oracle") returns
Driver name : Oracle (OCI)
Driver version: 1.3-1
Client version: 12.1.0.2.0

Try code like:
library(DBI)
library(ROracle)
drv <- Oracle()
con <- dbConnect(drv, 'cj', 'welcome', 'localhost:1521/orclpdb1')
dbGetQuery(con,"select count(*) from dual")
The connect string components are related to the {host}:1521/?service_name values you used with SQLAlchemy. Use a TNS alias or Easy Connect String, the same as other C based Oracle drivers, e.g. https://cx-oracle.readthedocs.io/en/latest/user_guide/connection_handling.html#connection-strings
The current ROracle code is at https://www.oracle.com/database/technologies/roracle-downloads.html There are some packaging glitches with uploading to CRAN and the CRAN maintainers haven't been responsive about resolving them.
ROracle still needs Oracle Client libraries such as from Oracle Instant Client.

How do I connect Python to my Postgres Server?

I have been having major trouble connecting my python shell to my postgres. I am doing this on windows. I have downloaded psycopg2 and everything for this to process, however it still is not working.
import psycopg2
conn=psycopg2.connect("dbname = 'test' user ='postgres' host ='localhost' password = 'mypassword'")
It gives me an error telling me that the database "test" does not exist, however it does! If you guys have any advice at all on what I should test out, that would be amazing. Thank you!

You can layout connection parameters as a string and pass it to the connect() function as like:
conn = psycopg2.connect("dbname=test user=postgres password=postgres")
Or you can use a list of keyword arguments like
conn = psycopg2.connect(host="localhost",database="test", user="postgres", password="postgres")
If its still fails then you should check on PostgreSQL side. You should try to connect the db in question using command line and see if error re appears or not. if it appears then something is missing on DB server side.

cx_Oracle LDAP Connection String syntax

With JDBC, we can use the following syntax to connect to an Oracle database over an LDAP connection:
jdbc:oracle:thin:#ldap://host:1234/service_name,cn=OracleContext,dc=org,dc=com
How can I connect over LDAP using cx_oracle?

I ended up going with jaydebeapi.
import pandas as pd
import jaydebeapi
import jpype
import os
import sys
def run(f_name,command,username,pw ):
jar='ojdbc8.jar'
args = '-Djava.class.path=%s' % jar
jvm_path = jpype.getDefaultJVMPath()
jpype.startJVM(jvm_path, args)
con = jaydebeapi.connect("oracle.jdbc.driver.OracleDriver", "jdbc:oracle:thin:#ldap://server.prod.company.com:3060/service,cn=OracleContext,dc=prod,dc=company,dc=com",[username, pw], jar)
try:
df= pd.read_sql(command,con)
df.to_excel(f_name)
print(df)
except Exception as e:
print(e)
finally:
con.close()
def Run_Program(myvars):
os.chdir(sys._MEIPASS)
f_name = myvars.MyFileName
command = myvars.plainTextEdit_CSVString.toPlainText()
username = myvars.lineEdit_UserName.text()
pw = myvars.lineEdit_Password.text()
run(f_name,command,username,pw )
Saving the ojdbc8.jar file from Oracle Client in the same folder and specifying the location in the code. And also downgrading the module JPype1 to JPype1==0.6.3 (its installed as a requirement for jaydebeapi )
This worked well for packaging using pyinstaller so that it could be shared. (i created a pyqt5 UI for user to use.

Here are my two cents using Python 3.7 and cx_Oracle v.8.2.0 on Win 10.
I wanted to issue queries to an Oracle database using Python, and what I already had was :
a username (or schema)
a password
a JDBC connection string that looked like:
jdbc:oracle:thin:#ldap://[LDAPHostname1]:[LDAPPort1]/[ServiceName],[DomainContext] ldap://[LDAPHostname2]:[LDAPPort2]/[ServiceName],[DomainContext]
where the [DomainContext] was of the form cn=OracleContext,dc=foo,dc=bar
First, you have to install cx_Oracle by following the Oracle documentation.
Note that:
cx_Oracle requires a series of library files that are part of the Oracle Instant Client "Basic" or "Basic Light" package (available here). Let's say we unzip the package under C:\path\to\instant_client_xx_yy
Depending on the platform you're on, some other requirements are to be filled (like installing some Visual Studio redistributable on Windows)
For the LDAP part, there are two configuration files that are required:
sqlnet.ora : This is the profile configuration file for Oracle, but mine was simply containing :
NAMES.DIRECTORY_PATH = (LDAP)
It tells the library to resolve names using LDAP only.
ldap.ora : This file tells where to look for when resolving names using LDAP. I knew I was accessing two OID servers, so mine was of the form :
DIRECTORY_SERVERS=([LDAPHostname1]:[LDAPPort1], [LDAPHostname2]:[LDAPPort2])
DEFAULT_ADMIN_CONTEXT="dc=foo,dc=bar"
DIRECTORY_SERVER_TYPE=oid
Important Note : I had to remove the cn=OracleContext from the DEFAULT_ADMIN_CONTEXT entry in order to make the name resolution work
Let's say those two files were saved under C:\path\to\conf
And now comes the Python part. I used the cx_Oracle.init_oracle_client() method in order to point to the library and configuration files. (Note that there are other ways to give cx_Oracle access to those files, like setting environment variables or putting those in predefined places. This is explained under the install guide)
Here is a little sample code:
import cx_Oracle
# username and password retrieved here
cx_Oracle.init_oracle_client(lib_dir=r'C:\path\to\instant_client_xx_yy', config_dir=r'C:\path\to\conf')
try:
with cx_Oracle.connect(user=username, password=password, dsn='[ServiceName]') as connection:
cursor = connection.cursor()
cursor.execute('SELECT * FROM ALL_TAB_COLUMNS')
# Outputs tables and columns accessible by the user
for row in cursor:
print(row[1], '-', row[2])
cursor.close()
except cx_Oracle.DatabaseError as e:
print("Oracle Error", e)

The short answer is that you use an ldap.ora configuration file and specify that it is to be used in your sqlnet.ora configuration file. Although this link talks about creating a database link and not directly connecting, the same principle applies and you can connect using any of the services referenced in your LDAP server.
http://technologydribble.info/2015/02/10/how-to-create-an-oracle-database-link-using-ldap-authentication/
Some more official documentation on how it works can be found here:
https://docs.oracle.com/cd/B28359_01/network.111/b28317/ldap.htm

Connect Hive Kerberos authentication using pyhs2 python

I am trying to connect to Hive with Kerberos authentication. But I am getting an error 'NotImplementedError: authMechanism is either not supported or not implemented'
I guess I need to set authMechanism to Kerberos somehow.
import pyhs2
with pyhs2.connect(host='wx0000',
port=10000,
authMechanism="Kerberos",
user='xxxxx',
password='******',) as conn:

From the source authMechanism is case sensitive, so you'll need it to be "KERBEROS".

This connection string will work as long as the user running the script has a valid kerberos ticket or key tab:
import pyhs2
with pyhs2.connect(host='beeline_hostname',
port=10000,
authMechanism="KERBEROS") as conn:
with conn.cursor() as cur:
print cur.getDatabases()
Username, password and any other configuration parameters are not passed through the KDC.

Python connect to Hive use pyhs2 and Kerberos authentication

I'm connecting Hive use pyhs2. But the Hive server required Kerberos authentication. Anyone knows how to convert the JDBC string to pyhs2 parameter? Like:
jdbc:hive2://biclient2.server.163.org:10000/default;principal=hive/app-20.photo.163.org#HADOOP.HZ.NETEASE.COM?mapred.job.queue.name=default

I think it will be something like this:
pyhs2.connect(host='biclient2.server.163.org',
port=10000,
authMechanism="KERBEROS",
password="something",
user='your_user#HADOOP.HZ.NETEASE.COM')
I'm also doing the same, I still not succeed, but at least having a meaningful errorcode:
(Server hive/xxx#yyy.COM not found in Kerberos database)

This connection string will work as long as the user running the script has a valid kerberos ticket:
import pyhs2
with pyhs2.connect(host='biclient2.server.163.org',
port=10000,
authMechanism="KERBEROS") as conn:
with conn.cursor() as cur:
print cur.getDatabases()
Username, password and any other configuration parameters are not
passed through the KDC.