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Python update query in mariadb

I am trying to update my mariadb table via python code .While compile the query nothing happen in my database. please check below code and let me know where i made mistake in update function
import mariadb
connection= mariadb.connect(user="user1", database="db1", host="ippp" ,password="pass")
cursor= connection.cursor()
cursor.execute("UPDATE product_options_combinations SET quantity=5944 WHERE item_code ='31628'")
cursor.close()
connection.close()

Hello here I have a clean code example for you. How to update it.
import pymysql
# Create a connection object
# IP address of the MySQL database server
Host = "localhost"
# User name of the database server
User = "user"
# Password for the database user
Password = ""
database = "GFG"
conn = pymysql.connect(host=Host, user=User, password=Password, database)
# Create a cursor object
cur = conn.cursor()
query = f"UPDATE PRODUCT SET price = 1400 WHERE PRODUCT_TYPE = 'broadband'"
cur.execute(query)
#To commit the changes
conn.commit()
conn.close()

You just need to add connection.commit() to your code, but I recommend you use a parametrized SQL preferably with a list of tuples,more of which might be added if needed, along with cursor.executemany() as being more performant for DML statements such as
import mariadb
connection= mariadb.connect(user="user1",
password="pass",
host="ippp",
port=3306,
database="db1")
cursor= connection.cursor()
dml="""
UPDATE product_options_combinations
SET quantity=%s
WHERE item_code =%s
"""
val=[
(5944,'31628')
]
cursor.executemany(dml,val)
connection.commit()
cursor.close()
connection.close()

Are you sure that the connection is working properly?
Have you tried to implement a try and catch routine to print mariadb errors?
Something like this:
# Connect to MariaDB Platform
import mariadb
try:
conn = mariadb.connect(
user="user",
password="password",
host="xx.xx.xx.xx",
port=3306,
database="db_name"
)
except mariadb.Error as e:
print(f"Error connecting to MariaDB Platform: {e}")
sys.exit(1)

sqlite3 add row to table doesnt add no errors

I have an SQLite3 database that I want to add to with python, this is the code i have to add a row
def create_connection(db_file):
""" create a database connection to a SQLite database """
conn = None
try:
conn = sqlite3.connect(db_file)
return conn
except Error as e:
print(e)
def add_password(conn, data):
"""
Create an entry into the password database
"""
try:
sql = 'INSERT INTO passwords(added,username,password,website,email) VALUES(?,?,?,?,?)'
cur = conn.cursor()
cur.execute(sql, data)
print('done')
return cur.lastrowid
except Error as e:
print(e)
connection = create_connection('passwords.db')
data = (datetime.now(), 'SomeUsername', 'password123', 'stackoverflow.com', 'some#email.com')
add_password(connection, data)
When I run it prints done and ends, there are no errors. However, when I open the database to view the table, it has no entries.
If I open the database and run the same SQL code
INSERT INTO passwords(added,username,password,website,email)
VALUES('13-5-2020', 'SomeUsername', 'password123', 'stackoverflow.com', 'some#email.com')
it adds to the table. So it must be a problem with my python code. How do I get it to add?

Just make conn.commit() after executing query. It should work

Can not write on a table in redshift

I am trying to copy a file from S3 to redshift table but I am unable to do so. However, I can read from the table so I know that my connection is okay.
Please help me to figure out the problem.
def upload_redshift():
conn_string = passd.redshift_login['login'] //the connection string containing dbname, username etc.
con = psycopg2.connect(conn_string);
sql = """FROM 's3://datawarehouse/my_S3_file' credentials 'aws_access_key_id=***;aws_secret_access_key=***' csv ; ;"""
try:
con = psycopg2.connect(conn_string)
logging.info("Connection Successful!")
except:
raise ValueError("Unable to connect to Redshift")
cur = con.cursor()
try:
cur.execute(sql)
logging.info(" Copy to redshift executed successfully")
except:
raise ValueError("Failed to execute copy command")
con.close()
I am getting Copy to redshift executed successfully message but nothing is happening in my table.

Try the following,
sql = "copy table_name FROM 's3://datawarehouse/my_S3_file' credentials 'aws_access_key_id=***;aws_secret_access_key=***' csv ;"
Also, try creating the connection under "connections tab" and use PostgresHook with aws_access_key_id and key as variables, something like below which enables to store the details encrypted within airflow,
pg_db = PostgresHook(postgres_conn_id='<<connection_id>>')
src_conn = pg_db.get_conn()
src_cursor = src_conn.cursor()
src_cursor.execute(sql)
src_cursor.commit()
src_cursor.close()
Also, you can use s3_to_redshift_operator operator and execute it as a task,
from airflow.operators.s3_to_redshift_operator import S3ToRedshiftTransfer
T1 = S3ToRedshiftTransfer(
schema = ‘’,
table = ‘’,
s3_bucket=‘’,
s3_key=‘’,
redshift_conn_id=‘’, #reference to a specific redshift database
aws_conn_id=‘’, #reference to a specific S3 connection
)

Is there a way to insert dataframe into mysql using pymysql?

I have this:
import pymysql
import pymysql.cursors
host = "localhost"
port=3306
user = "db"
password='pass'
db='test'
charset='utf8mb4'
cursorclass=pymysql.cursors.DictCursor
try:
connection= pymysql.connect(host=host,port=port,user=user,password=passw,db=db,charset=charset,cursorclass=cursorclass)
Executor=connection.cursor()
except Exception as e:
print(e)
sys.exit()
I tried using the pandas to_sql(), but it is replacing the values in the table with the latest one. I want to insert the values into the table using the Pandas, but I want to avoid the duplicate entries and if any then it should get passed.

It might be possible to pickle the dataframe, and insert it into a table under a column of type BLOB. If you go this way, you'd have to depickle the result returned by mysqld
EDIT: I see what you are trying to do now. Here is a possible solution. Let me know if it works!
# assume you have declared df and connection
records = df.to_dict(orient = 'records')
for record in records:
sql = "INSERT INTO mytable ({0}) \
VALUES ({1})".format(record.keys(), record.values())
curs = connection.cursor()
try:
curs.execute(sql)
curs.close()
except:
break #handle/research the error

Sqlite insert query not working with python?

I have been trying to insert data into the database using the following code in python:
import sqlite3 as db
conn = db.connect('insertlinks.db')
cursor = conn.cursor()
db.autocommit(True)
a="asd"
b="adasd"
cursor.execute("Insert into links (link,id) values (?,?)",(a,b))
conn.close()
The code runs without any errors. But no updation to the database takes place. I tried adding the conn.commit() but it gives an error saying module not found. Please help?

You do have to commit after inserting:
cursor.execute("Insert into links (link,id) values (?,?)",(a,b))
conn.commit()
or use the connection as a context manager:
with conn:
cursor.execute("Insert into links (link,id) values (?,?)", (a, b))
or set autocommit correctly by setting the isolation_level keyword parameter to the connect() method to None:
conn = db.connect('insertlinks.db', isolation_level=None)
See Controlling Transactions.

It can be a bit late but set the autocommit = true save my time! especially if you have a script to run some bulk action as update/insert/delete...
Reference: https://docs.python.org/2/library/sqlite3.html#sqlite3.Connection.isolation_level
it is the way I usually have in my scripts:
def get_connection():
conn = sqlite3.connect('../db.sqlite3', isolation_level=None)
cursor = conn.cursor()
return conn, cursor
def get_jobs():
conn, cursor = get_connection()
if conn is None:
raise DatabaseError("Could not get connection")
I hope it helps you!