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Python alternative to R RJDBC connection to SQL

I have a R code which connect to the Vertica database using RJDBC driver. The code is following:
library(RJDBC)
#for vertica save
user = "myuser"
pwd = "mypwd"
driver<- JDBC(driverClass="com.vertica.jdbc.Driver", classPath=Pathto thedriver")
connection<- dbConnect(driver, databasewithport, user, pwd)
sql_code = paste("SELECT .....")
mydata= dbGetQuery(connection, sql_code )
I am searching for a solution that helps do the same thing but using Python. I found the following link, but do not understand which example to use and what else to do. As I understood here no need to connect to the RJDBC driver. Could you help to find the solution which gives the same output as R version.
The code below works well, however, data is retrieved as one value, to get another I need to change ....cur.fetchone()[ANYNUMBER]). How can I get a data frame of the SQL code?
import vertica_python
conn_info = {'host': '127.0.0.1',
'port': 5433,
'user': 'some_user',
'password': 'some_password',
'database': 'vdb',
'connection_load_balance': True}
# Server enables load balancing
with vertica_python.connect(**conn_info) as conn:
cur = conn.cursor()
cur.execute("SELECT NODE_NAME FROM V_MONITOR.CURRENT_SESSION")
print("Client connects to primary node:", cur.fetchone()[0])
cur.execute("SELECT SET_LOAD_BALANCE_POLICY('ROUNDROBIN')")

First of all you will need to install the vertica-python package:
pip install vertica-python
Next, you need to create a connection and perform the query. When retrieving the query results, you can (1) load them all or (2) process them one by one.
import vertica_python
conn_info = {'host': '127.0.0.1',
'port': 5433,
'user': 'myuser',
'password': 'mypass',
'database': 'vdb',
'connection_load_balance': True}
with vertica_python.connect(**conn_info) as connection:
cur = conn.cursor()
cur.execute("SELECT NODE_NAME FROM V_MONITOR.CURRENT_SESSION")
# (1) If you want to load all the results in-memory
data = cur.fetchall()
print(data)
# (2) If you want to process one by one
for row in cur.iterate():
print(row)

How to connect to Oracle-RAC using SCAN in python?

I use cx_Oracle module to connect to standalone Oracle server as follows
import cx_Oracle
CONN_INFO = {
'host': 'xxx.xx.xxx.x',
'port': 12345,
'user': 'user_name',
'psw': 'your_password',
'service': 'abc.xyz.com',
}
CONN_STR = '{user}/{psw}#{host}:{port}/{service}'.format(**CONN_INFO)
connection = cx_Oracle.connect(CONN_STR)
but as scan IP doesn not have machine and its own username passoword, How do we connect?

Es described in the documentation, you can simple use the name defined in tnsnames.ora.
Say your RAC tnsnames entry is called MAXIMIR than you can connect with
con = cx_Oracle.connect("my_usr", "my_pwd", "MAXIMIR", encoding="UTF-8")
alternatively you may pass the whole connection string in a dns variable
dsn = """(DESCRIPTION=
(FAILOVER=on)
(ADDRESS_LIST=
(ADDRESS=(PROTOCOL=tcp)(HOST=scan1)(PORT=1521))
(ADDRESS=(PROTOCOL=tcp)(HOST=scan2)(PORT=1521)))
(CONNECT_DATA=(SERVICE_NAME=MAXIMIR)))"""
connection = cx_Oracle.connect("my_usr", "my_pwd", dsn, encoding="UTF-8")

How to get key(column name)-value pair from a Select query using default connection in Django

I have 4 applications in one Django Project. I am using the default Postgres database connection which I have included it in my setting.py file.
The object django.db.connection represents the default database connection. To use the database connection, I call connection.cursor() to get a cursor object. Then, I call cursor.execute(sql, [params]) to execute the raw Postgres queries and cursor.fetchone() or cursor.fetchall() to return the resulting rows.
Now, in one application I want to use the (connection.cursor(cursor_factory = psycopg2.extras.RealDictCursor)) to get the records in a (key(column name), value) pair, which is provided by psycopg2.connect but the default connection that I have is not compatible with cursor_factory = psycopg2.extras.RealDictCursor.
How do I get a (key(column name), value) pair from the database by using the default connection?
In setting.py
`DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'OPTIONS' : {
'options': '-c search_path=django,public'
},
'NAME': 'postgres',
'USER': 'abc',
'PASSWORD': 'password!',
'HOST': '',
'PORT': '',
}
}
`
In python file .py
from django.db import connection
cur = connection.cursor(cursor_factory = psycopg2.extras.RealDictCursor)
cur.execute("SELECT * FROM sometable")
data= cur.fetchall()
ERROR: cursor() got an unexpected keyword argument 'cursor_factory'

You have to get an underlying postgres connection, ensure it is established and then you can specify custom cursor_factory.
from django.db import connections
import psycopg2
def scan_tables(app):
conn = connections['default']
conn.ensure_connection()
with conn.connection.cursor(cursor_factory=psycopg2.extras.RealDictCursor) as cursor:
cursor.execute("SELECT table_name, column_name "
"FROM information_schema.columns AS c "
"WHERE table_name LIKE '{}_%'".format(app))
print(cursor.fetchall())
scan_tables('django')
This is an adapted answer from https://stackoverflow.com/a/48844401/803174 #kert just putting different cursor type.

Python mysql.connector connect to DB in specific directory xampp

I have an XAMPP DB I am trying to connect to with mysql.connector on a Red Hat Linux server. The issue is the DB is only accessible from /opt/lampp/bin/mysql. I cannot find a way to specify path with the mysql.connector module.
My code is:
import mysql.connector
config = {
'user': 'user',
'password': '*****',
'host': '127.0.0.1',
'database': 'test',
'raise_on_warnings': True,
}
cnx = mysql.connector.connect(**config)
cursor = cnx.cursor()
query = "show columns from Table1"
cursor.execute(query)
lst = []
for line in cursor:
lst.append(line[0])
query2 = "select * from Table1 limit 5"
lst2 = []
cursor.execute(query2)
for line in cursor:
lst2.append(dict(zip(lst, line)))
print(lst2)
cnx.close()
Right now I am getting an error when running it mysql.connector.errors.InterfaceError: Failed parsing handshake; end byte not present in buffer but I am assuming that it is probably because I am not specifying path to database.
Thanks

I am finding evidence which suggests that this problem is related to MySQL version 5.5.8. What version of MySQL are you running?

Oracle connection string with at sign # in pasword

I have a code that connect to oracle using connection string:
conn = cx_Oracle.connect('username/password#server:port/services')
But the problem is my password contain # character so it may become
conn = cx_Oracle.connect('username/p#ssword#server:port/services')
it return
DatabaseError: ORA-12154: TNS:could not resolve the connect identifier
specified
I use Django with Oracle with this settings
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.oracle',
'NAME': 'Services',
'USER': 'user',
'PASSWORD': 'p#ssword',
'HOST': 'ip',
'PORT': 'port',
}
}
I cant change password :( Does anyone know this problem?

I haven't tried cx_Oracle, but you might be able to connect by specifying the individual parameters -
conn = cx_Oracle.connect(user='username', password='p#ssword', dsn='server:port/services')
OR
dsn_tns = cx_Oracle.makedsn('server', 'port', 'services')
conn = cx_Oracle.connect(user='username', password='p#ssword', dsn=dsn_tns)

You can use any of the following way based on Service Name or SID whatever you have.
With SID:
dsn_tns = cx_Oracle.makedsn('server', 'port', 'sid')
conn = cx_Oracle.connect(user='username', password='p#ssword', dsn=dsn_tns)
OR
With Service Name:
dsn_tns = cx_Oracle.makedsn('server', 'port', service_name='service_name')
conn = cx_Oracle.connect(user='username', password='p#ssword', dsn=dsn_tns)

Does this work?
conn = cx_Oracle.connect('username/"p#ssword"#server:port/services')

FYI: This was a long-standing bug in Django. The first stable version containing the fix is v2.1

All the answers mentioned here did not work for SQLAlchemy.
Parsing the characters to create a valid URL worked:
from sqlalchemy.engine import create_engine
import urllib.parse
url_password = urllib.parse.quote_plus(password)
connection_string = f"oracle+cx_oracle://{username}:{url_password}#{server}:{port}/?service_name={service}"
connection = create_engine(connection_string)
Should probably do the same with the other components of the connection string.