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Update images in SQL from Python

I have an issue trying to upload files from Python to my database. I can insert the binary data into the table just fine using %s, but when I try to update the record, I am unable to get this to work. Am I doing something wrong?
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x01\x90\x00\x00\x00\xc8\x08\x06\x00\' at line 8
Now, I know this is because the bytestring contains a ' so this doesn't work, it excepts, and leaves some security holes open if it were to work:
dbc.execute(f"""UPDATE userdata SET
emailaddr ='{email}',
firstname ='{namee}',
lastname ='{laste}',
username ='{usere}',
password ='{passe}',
phonenum ='{phone}',
photoimg ='{u_pho}'
WHERE user_id = '{user_ident}';""")
but I'm wondering if I can update a value like this:
insertcommand = f"""UPDATE userdata SET (emailaddr,firstname,lastname,username,password,phonenum,photoimg) VALUES (%s, %s, %s, %s, %s, %s, %s) WHERE user_id = '{user_ident}'"""
insertrecord = email,namee,laste,usere,passe,phone,u_pho
dbc.execute(insertcommand,insertrecord)
How would I go about updating bytestrings in MySQL with Python?

Can't See Data In pgAdmin after using python code

I am trying to take a dataframe and import it into a postgresql database. I've done this before and can always see the data in the database using pgAdmin. However, this time, there's no data visable in pgAdmin.
This is the SQL code I've used to create my table in the postgresql database:
CREATE TABLE Twitterapp
(
tweetid character varying(255),
tweettext character varying(255),
tweetretweetct integer,
tweetfavoritect integer,
tweetsource character varying(255),
tweetcreated character varying(255),
userid character varying(255),
userscreen character varying(255),
username character varying(255),
usercreatedt character varying(255),
user_desc character varying(255),
userfollowerct integer,
userfriendsct integer,
userlocation character varying(255),
usertimezone character varying(255)
)
WITH (
OIDS=FALSE
);
Then, using the sqlalchemy library in python, I tried to push my dataframe to the database:
#First attempt to load data
engine =create_engine('postgresql://username:password#link:5432/db_name')
conn = engine.connect()
a.to_sql('public.twitterapp', con=conn, if_exists='replace',
index=False)
Since that operation was successful, I try to read a table from the database to check sure it worked:
##call data from database
result_set = engine.execute("SELECT * FROM twitterapp")
for r in result_set:
print(r)
This code successfully returns the data in my dataframe but I still can't see it in my pgAdmin database. So I tried this second approach:
b = a.values.tolist()
sql2 = """INSERT INTO twitterapp VALUES(%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s);"""
conn = psycopg2.connect("dbname='db_name' user='username' host='link' password='password'")
c = conn.cursor()
for row in b:
c.execute(sql2, row)
print(row)
conn.commit()
Again, it successfully executes (ie, doesn't throw an error) but no data shows in pgAdmin.
What am I doing wrong?!

If you can show data during the session but not from pgAdmin (a different session) it's sure that your mistake is a wrong commit.
I'm not an expert of sqlalchemy but I think you have to read how to manage the session and how to commit it.
This is a good link:
http://docs.sqlalchemy.org/en/latest/orm/session_basics.html
You have to create a session object and execute a commit command:
session.commit()

You should check the port in psql if it's right or not. In my case local postgresql was listening to port 5433

PostgreSQL Schema "www" does not exist?

From the PostgreSQL documentation if you do a INSERT without specifying a schema it should be a public schema.
conn = psycopg2.connect(dbname = 'orion',
host = 'localhost',
port = 5432,
user = 'earthling',
password = 'mysupersecretpassword')
sql = conn.cursor()
def INSERT(table, info, text):
date = datetime.date.today()
query = "INSERT INTO %s (info, text, date) " \
"VALUES (%s, %s, %s)" %(table, info, text, date)
sql.execute(query)
INSERT("main", "www.capecod.edu", "test")
For some reason I'm seeing the following error?
psycopg2.ProgrammingError: schema "www" does not exist

You are using string interpolation to create the query. This is what psycopg2 executes:
INSERT INTO main (info, text, date)
VALUES (www.capecod.edu, test, 2015-09-12)
If it's not obvious what's wrong here, it's that none of the values are quoted. Here is the properly quoted version:
INSERT INTO main (info, text, date)
VALUES ('www.capecod.edu', 'test', '2015-09-12')
The error is caused by the unquoted www.capecod.edu. Due to the dots, it's being interpreted as schema.table.column.
The "right" way to do this is with a parameterized query.
query = "INSERT INTO main (info, text, date) VALUES (%s, %s, %s)"
params = (info, text, date)
sql.execute(query, params)
psycopg2 will figure out what should be quoted and how. This is a safer option than simply interpolating the string yourself, which often leaves you open to SQL injection attack.
http://initd.org/psycopg/articles/2012/10/01/prepared-statements-psycopg/
Unfortunately, you can't just toss identifiers such as the table name in as a parameter, because then they are quoted as string values, which is bad SQL syntax. I found an answer (python adds "E" to string) that points to psycopg2.extensions.AsIs as a way to pass identifiers such as table names safely as parameters. I wasn't able to make this work in my testing, though.
If you go the AsIs route, you should be cautious about checking the table names are valid, if they somehow come from user input. Something like
valid_tables = ["main", "foo", "bar", "baz"]
if table not in valid_tables:
return False

How to insert Records of data into MySQL database with python?

I have an form which has FirstName, Lastname, Age and Gender. I am using MySQL db.
While using MySQl db, do we need to create table , do the insert operation in the single pythonic script ?
For example :
#!/usr/bin/python
import MySQLdb
db = MySQLdb.connect("localhost", "usename", "password", "TESTDB")
cursor = db.cursor()
cursor.execute ( """
CREATE TABLE PERSON
(
F_NAME CHAR(20) NOT NULL,
L_NAME CHAR(20),
AGE INT,
GENDER CHAR(4)
)
""")
cursor.execute( """
INSERT INTO PERSON (F_NAME, L_NAME, AGE, GENDER)
VALUES
('Neeraj','Lad','22','Male'),
('Vivek','Pal','24','Male')
""")
print cursor.rowcount
Edited Code:
#!/usr/bin/python
import MySQLdb
import cgi
print "Content-type: text/html\n"
form = cgi.FieldStorage()
f_Name = form.getvalue('firstname', '')
l_Name = form.getvalue('lastname', '')
age = form.getvalue('age', 0)
gender = form.getvalue('gender', '')
db = MySQLdb.connect(host="", user="", password="", db="")
cursor = db.cursor()
sql = "INSERT INTO PERSON (F_NAME, L_NAME, Age, Gender) VALUES (%s, %s, %s, %s)" %(f_name, l_name, age, gender)
cursor.execute(sql)
db.commit()
db.close()

I'm not 100% clear on what you're asking, but I'll take a guess.
You have to create a table exactly once in the database before you can insert into it.
If your Python script is talking to a brand-new database each time it runs, then it needs a CREATE TABLE statement.
If your Python script might be talking to a brand-new database, but will usually be talking to an already-existing one, then you can use CREATE TABLE IF NOT EXISTS.
But, except in toy learning projects, both of these are rare. Normally, you create the database once, then you write Python scripts that connect to it and assume it's already been created. In that case, you will not have a CREATE TABLE statement in your form handler.
If you're asking about inserting multiple values in a single INSERT statement… normally, you won't be inserting hard-coded values like 'Neeraj', but rather values that you get dynamically (e.g., from the web form). So you will be using parameterized SQL statements like this:
cursor.execute("""
INSERT INTO PERSON (F_NAME, L_NAME, AGE, GENDER)
VALUES (%s, %s, %s, %s)
""", (f_name, l_name, age, gender))
In that case, if you have, say, a list of 4-tuples, each representing a person, and you want to insert all of them, you do that not by putting multiple copies of the parameter lists in the SQL statement, but by putting a single parameter list, and using the executemany function:
cursor.execute("""
INSERT INTO PERSON (F_NAME, L_NAME, AGE, GENDER)
VALUES (%s, %s, %s, %s)
""", list_of_people)

You only need to create the table once. You can do that using the mysql CLI tool, or phpmyadmin, or python/MySQLdb, or by some other method.
CREATE TABLE PERSON will raise an error if the table PERSON already exists. If you'd like a way to create it in your python script, use IF NOT EXISTS, so subsequent runs of your program do not raise an error:
cursor.execute ( """
CREATE TABLE IF NOT EXISTS PERSON
(
F_NAME CHAR(20) NOT NULL,
L_NAME CHAR(20),
AGE INT,
GENDER CHAR(4)
)
""")

Can't execute an INSERT statement in a Python script via MySQLdb

I'm trying to execute a basic INSERT statement on a MySQL table from a Python script using MySQLdb. My table looks like this:
CREATE TABLE `testtable` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`testfield` varchar(255) NOT NULL,
PRIMARY KEY (`id`)
)
Running this query from the MySQL command line works fine:
INSERT INTO `testtable` (`id`, `testfield`) VALUES (NULL, 'testvalue');
But when I try to execute the query from a Python script, no rows get inserted. Here's my code:
conn = MySQLdb.connect(host=db_host, port=db_port, user=db_user, passwd=db_password, db=db_database)
cursor = conn.cursor ()
cursor.execute ("INSERT INTO `testtable` (`id`, `testfield`) VALUES (NULL, 'testvalue')")
print "Number of rows inserted: %d" % cursor.rowcount
cursor.close()
conn.close()
Oddly, this will print "Number of rows inserted: 1." I can also confirm that this query increments the ID field, because when I add another row via the command line, the value of its ID is the same as if the Python script had successfully inserted its rows. However, running a SELECT query returns none of the rows from the script.
Any idea what's going wrong?

You either need to set conn.autocommit(), or you need to do conn.commit() - see the FAQ

you need to commit:
conn.commit()
http://mysql-python.sourceforge.net/FAQ.html#my-data-disappeared-or-won-t-go-away