i want to retrieve image from database using python but i have a problem where i execute this code
import mysql.connector
import io
from PIL import Image
connection= mysql.connector.connect(
host ="localhost",
user ="root",
passwd ="pfe_altran",
database = "testes",
)
cursor=connection.cursor()
sql1 = "SELECT * FROM pfe WHERE id = 1 "
cursor.execute(sql1)
data2 = cursor.fetchall()
file_like2 = io.BytesIO(data2[0][0])
img1=Image.open(file_like2)
img1.show()
cursor.close()
connection.close()
and i have this error :
file_like2 = io.BytesIO(data2[0][0]) TypeError: a bytes-like object
is required, not 'int'
cursor.fetchall() returns a list of rows to your variable so you need to handle that using a looper
for row in data2:
file_like2 = io.BytesIO(row[0]) #assumming row[0] contains the byte form of your image
you can use cursor.fetchmany(size=1) or cursor.fetchone() if you know that your query will return only a single row or if you know that you only need one row, this way you can manipulate it directly and not use the loop.
Related
I have been searching but I didn't find a simple way to draw a graph from a SQL request.
For example I have this code, and I want to make a bar chart from the result of the request :
import pymysql as sql
from dash import dcc
DB = ...
HOST = ...
USER = ...
PASSWORD = ...
connection = sql.connect(host=HOST,
port=x,
user=USER,
password=PASSWORD,
database=DB,
cursorclass=sql.cursors.DictCursor)
with connection.cursor() as cursor:
# Read a single record
sql = 'SELECT COUNT(*) AS count FROM table'
cursor.execute(sql)
result = cursor.fetchone()
print(result)
Also, I would like to update the chart regularly.
Thank you
I am having a problem with reading my csv file into the MySQL database. I have tried a number of solutions, but the errors just keep changing and the code isn't working. This same code had worked with another csv file, so I'm thinking I might be doing something wrong with this one?
Here is my code
from database_access import *
from builtins import bytes, int, str
import codecs
import csv
import requests
from urllib.parse import urlparse, urljoin
from bs4 import BeautifulSoup
import re
import cgi
import MySQLdb
import chardet
# from database_access import *
import MySQLdb
import simplejson
if __name__ == '__main__':
with open("SIMRA.csv",'r') as file:
reader = csv.reader(file)
#reader = csv.reader(text)
next(reader, None)
print ("project running")
#print (row[7])
#rowlist = []
all_links = []
all_project_ids = []
for row in reader:
if row[7] != "" and row[16] != "":
country = row[2]
city = row[8]
description = row[11] + '' + row[12]
title = row[7].replace("'", "''")
link = row[16]
#date_start = row[9]
#print a check here
print(title,description,country, city, link)
db = MySQLdb.connect(host, username, password, database, charset='utf8')
cursor = db.cursor()
new_project = True
proj_check = "SELECT * from Projects where ProjectName like '%" + title + "%'"
#proj_check = "SELECT * from Projects where ProjectName like %s",(title,)
#cur.execute("SELECT * FROM records WHERE email LIKE %s", (search,))
cursor.execute(proj_check)
num_rows = cursor.rowcount
if num_rows != 0:
new_project = False
url_compare = "SELECT * from Projects where ProjectWebpage like '" + link + "'"
#url_compare = "SELECT * from Projects where ProjectWebpage like %s",(link,)
cursor.execute(url_compare)
num_rows = cursor.rowcount
if num_rows != 0:
new_project = False
if new_project:
project_insert = "Insert into Projects (ProjectName,ProjectWebpage,FirstDataSource,DataSources_idDataSources) VALUES (%s,%s,%s,%s)"
cursor.execute(project_insert, (title, link,'SIMRA', 5))
projectid = cursor.lastrowid
print(projectid)
#ashoka_projectids.append(projectid)
db.commit()
ins_desc = "Insert into AdditionalProjectData (FieldName,Value,Projects_idProjects,DateObtained) VALUES (%s,%s,%s,NOW())"
cursor.executemany(ins_desc, ("Description", description, str(projectid)))
db.commit()
ins_location = "Insert into ProjectLocation (Type,Country,City,Projects_idProjects) VALUES (%s,%s,%s,%s)"
cursor.execute(ins_location, ("Main", country,city, str(projectid)))
db.commit()
else:
print('Project already exists!')
print(title)
all_links.append(link)
#print out SIMRA's links to a file for crawling later
with open('simra_links', 'w', newline='') as f:
write = csv.writer(f)
for row in all_links:
columns = [c.strip() for c in row.strip(', ').split(',')]
write.writerow(columns)
When I ran this, I got the following error:
File "/usr/lib/python3.8/codecs.py", line 322, in decode
(result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xa3 in position 898: invalid start byte
I did some research and tried handling the encoding error by adding different forms of encoding, as seen here - UnicodeDecodeError: ‘utf8’ codec can’t decode byte 0xa5 in position 0: invalid start byte, and Python MySQLdb TypeError: not all arguments converted during string formatting. Added this in this in the csv open parameter -
with open("SIMRA.csv", 'r', encoding="cp437", errors='ignore') as file:
Running the code with these different encoding options came up with a different error:
MySQLdb._exceptions.ProgrammingError: not all arguments converted during bytes formatting
Further research suggested using tuples or lists in order to address this problem, so I added these in the 'select' function in the code, as suggested here - Python MySQLdb TypeError: not all arguments converted during string formatting and in the Python SQL documentation here - PythonMySqldb
So the select query became:
proj_check = "SELECT * from Projects where ProjectName like %s",(title,)
cursor.execute(proj_check)
num_rows = cursor.rowcount
if num_rows != 0:
new_project = False
url_compare = "SELECT * from Projects where ProjectWebpage like %s",(link,)
cursor.execute(url_compare)
num_rows = cursor.rowcount
if num_rows != 0:
new_project = False
When I ran the code, I came up with this Assertion Error and I have no idea what to do anymore.
File "/home/ros/.local/lib/python3.8/site-packages/MySQLdb/cursors.py", line 205, in execute
assert isinstance(query, (bytes, bytearray))
AssertionError
I have run out of ideas. It might be that I'm missing something small, but I can't figure this out now as I've been battling with this for two days now.
Can anyone help point out what I'm missing? It will be greatly appreciated. This code ran perfectly with another csv file. I am running this with Python 3.8 btw.
Have solved this now. I had to use a different encoding with the original code and this solved the problem. So, I changed the csv open parameter to:
with open("SIMRA.csv",'r', encoding="ISO-8859-1") as file:
reader = csv.reader(file)
Were you expecting £? You need to specify what the encoding of the file is. It may be "latin1". See the syntax of LOAD DATA for how to specify CHARACTER SET latin1.
I am trying to get a PyMySQL query in Lambda (Python 3.6) to return whether a user exists or not. I pass my slack user ID into the query. This is what I want to check in MySQL. I can run the same query through MySQL and it returns a 0, but for some reason, every time I call this query through lambda, it tells me the user exists (My database is empty). My query is function is this:
def userExists(user):
statement = f"SELECT EXISTS(SELECT 1 FROM slackDB.Assets WHERE userID LIKE '%{user}%')Assets"
tempBool = cursor.execute(statement, args=None)
conn.commit()
return tempBool
Here is the full code I am working with:
################################
# Slack Lambda handler.
################################
import sys
import logging
import os
import pymysql
import urllib
# Grab data from the environment.
BOT_TOKEN = os.environ["BOT_TOKEN"]
ASSET_TABLE = os.environ["ASSET_TABLE"]
REGION_NAME = os.getenv('REGION_NAME', 'us-east-2')
DB_NAME = "admin"
DB_PASSWORD = "somepassword"
DB_DATABASE = "someDB"
RDS_HOST = "myslackdb.somepseudourl.us-east-2.rds.amazonaws.com"
port = 3306
logger = logging.getLogger()
logger.setLevel(logging.INFO)
try:
conn = pymysql.connect(RDS_HOST, user=DB_NAME, passwd=DB_PASSWORD, db=DB_DATABASE, connect_timeout=5)
cursor = conn.cursor()
except:
logger.error("ERROR: Unexpected error: Could not connect to MySql instance.")
sys.exit()
# Define the URL of the targeted Slack API resource.
SLACK_URL = "https://slack.com/api/chat.postMessage"
def userExists(user):
statement = f"SELECT EXISTS(SELECT 1 FROM slackDB.Assets WHERE userID LIKE '%{user}%')Assets"
tempBool = cursor.execute(statement, args=None)
conn.commit()
return tempBool
def addUser(user):
statement = f"INSERT INTO `slackDB`.`Assets` (`userID`, `money`) VALUES ('{user}', '1000')"
tempBool = cursor.execute(statement, args=None)
conn.commit()
return tempBool
def lambda_handler(data, context):
# Slack challenge answer.
if "challenge" in data:
return data["challenge"]
# Grab the Slack channel data.
slack_event = data['event']
slack_userID = slack_event["user"]
slack_text = slack_event["text"]
channel_id = slack_event["channel"]
slack_reply = ""
# Ignore bot messages.
if "bot_id" in slack_event:
slack_reply = ""
else:
# Start data sift.
if slack_text.startswith("!networth"):
slack_reply = "Your networth is: "
elif slack_text.startswith("!price"):
command,asset = text.split()
slack_reply = f"The price of a(n) {asset} is: "
elif slack_text.startswith("!addme"):
if userExists(slack_userID):
slack_reply = f"User {slack_userID} already exists"
else:
slack_reply = f"Adding user {slack_userID}"
addUser(slack_userID)
# We need to send back three pieces of information:
data = urllib.parse.urlencode(
(
("token", BOT_TOKEN),
("channel", channel_id),
("text", slack_reply)
)
)
data = data.encode("ascii")
# Construct the HTTP request that will be sent to the Slack API.
request = urllib.request.Request(
SLACK_URL,
data=data,
method="POST"
)
# Add a header mentioning that the text is URL-encoded.
request.add_header(
"Content-Type",
"application/x-www-form-urlencoded"
)
# Fire off the request!
urllib.request.urlopen(request).read()
# Everything went fine.
return "200 OK"
I am typing '!addme' in slack and it always tells me the user exists. I have printed out my query statement and it is inputting my slack ID correctly. I have checked my table, and it is completely empty. I have run the query in MySQL and it returns a 0.
Does anyone have any ideas? Am I just derping this up on something easy? Any helps or hints is much appreciated.
Thanks,
I don't see a fetch from the cursor. Just the execute.
And the return from execute is the number of rows affected. For DML operations (INSERT/UPDATE/DELETE) that makes sense. But I wouldn't rely on the rows affected count for a SELECT.
In this case, the SELECT EXISTS query is going to either return a row, or throw an error. But the fact that the query returns a row doesn't tell us anything about the value of the Assets column.
From the query, it looks like we want to fetch a row, and then determine if the Assets column contains a 0 or 1 (or NULL).
After the query execution, try cur.fetchone to retrieve the row.
We could also execute a simpler query, and then use a fetch to determine if a row is returned or not.
Hello I have win 10 Greece. I want to fetch same data (the path of a file) from mysql. The problem is while I retrieve the path instead of the name of the folder I came across with??????. A sample of the code is the following
import pymysql as MySQLdb
dbid = "client"
password = "pass"
database = "clients"
serverip = "192.168.168.150"
db = None
cur = None
try:
db = MySQLdb.connect(host=serverip, user=dbid, passwd=password, db=database, connect_timeout=20)
cur = db.cursor()
except MySQLdb.Error as e:
print("Cannot connect with the Data Base : "), e
query1 = "SELECT path FROM `instructions` WHERE clientmac ='%s'" % (str(5555))
try:
row = None
cur.execute(query1)
db.commit()
row = cur.fetchall()
except MySQLdb.Error as e:
print("Problem while Executing query :", query1, "error : ", e)
print(row)
db.close()
cur.close()
Python 3 uses Unicode so I thing that the problem is not from python but from phpmyadmin. The field path is “utf8_general_ci”. Everything looks fine but why instead of
'C:\\Users\\Γιαννης\\Documents\\Arduino' I am getting 'C:\\Users\\???????\\Documents\\Arduino'
I found the answer. I hat to but some additional coding before the execution of the query. I post the code below.
import pymysql as MySQLdb
dbid = "client"
password = "pass"
database = "clients"
serverip = "192.168.168.150"
socketip = "192.168.168.18"
db = None
cur = None
try:
db = MySQLdb.connect(host=serverip, user=dbid, passwd=password, db=database, use_unicode=True, connect_timeout=20)
cur = db.cursor()
except MySQLdb.Error as e:
print("Cannot connect with the Data Base : "), e
query1 = "SELECT path FROM `instructions` WHERE clientmac ='%s'" % (str(5555))
try:
row = None
db.set_charset('utf8')
cur.execute('SET NAMES utf8;')
cur.execute('SET CHARACTER SET utf8;')
cur.execute('SET character_set_connection=utf8;')
cur.execute(query1)
db.commit()
row = cur.fetchall()
except MySQLdb.Error as e:
print("Problem while Executing query :", query1, "error : ", e)
print(row)
db.close()
cur.close()
How can I escape the input to a MySQL db in Python3?
I'm using PyMySQL and works fine, but when I try to do something like:
cursor.execute("SELECT * FROM `Codes` WHERE `ShortCode` = '{}'".format(request[1]))
it won't work if the string has ' or ". I also tried:
cursor.execute("SELECT * FROM `Codes` WHERE `ShortCode` = %s",request[1])
The problem with this is that the library (PyMySQL) uses the formatting syntax for Python2.x, %, that doesn't work anymore.
I also found this possible solution
conn.escape_string()
in here, but I don't know where to add this code.
This is all I got:
import pymysql
import sys
conn = pymysql.connect( host = "localhost",
user = "test",
passwd = "",
db = "test")
cursor = conn.cursor()
cursor.execute("SELECT * FROM `Codes` WHERE `ShortCode` = {}".format(request[1]))
result = cursor.fetchall()
cursor.close()
conn.close()
Edit: I solved it! In PyMySQL the right way is like this:
import pymysql
import sys
conn = pymysql.connect(host="localhost",
user="test",
passwd="",
db="test")
cursor = conn.cursor()
text = conn.escape(request[1])
cursor.execute("SELECT * FROM `Codes` WHERE `ShortCode` = {}".format(text))
cursor.close()
conn.close()
Where the text = conn.escape(request[1]) line is what escapes the code. Found it inside PyMySQL code. There, request[1] is the input.
Although the "solved" answer works, it is not best practice. When using a library conforming to the Python DBI, you should be using bind variables rather than formatting a string and passing it to execute. There are dangers inherent in that methodology.
Therefore, this is the right way to do it:
cursor.execute("SELECT * FROM `Codes` WHERE `ShortCode` = %s", text)
Note that this is not a format string but a bind variable passed to the executing cursor.
For details: Python DBI PEP
Solved. In PyMySQL the right way is like this:
import pymysql
import sys
conn = pymysql.connect(host="localhost",
user="test",
passwd="",
db="test")
cursor = conn.cursor()
text = conn.escape(request[1])
cursor.execute("SELECT * FROM `Codes` WHERE `ShortCode` = {}".format(text))
cursor.close()
conn.close()
Where the text = conn.escape(request[1]) line is what escapes the code. Found it inside PyMySQL code. There, request[1] is the input.
Ready to use helper function
def mysql_insert(conn, table, row):
cols = ', '.join('`{}`'.format(col) for col in row.keys())
vals = ', '.join('%({})s'.format(col) for col in row.keys())
sql = 'INSERT INTO `{0}` ({1}) VALUES ({2})'.format(table, cols, vals)
conn.cursor().execute(sql, row)
conn.commit()
Usage example
insert_into(conn, 'people', {
'firstname': 'John',
'lastname': 'Doe',
'age': 18, })
Reference: https://github.com/PyMySQL/PyMySQL/blob/master/pymysql/cursors.py#L157-L158
def execute(self, query, args=None):
If args is a list or tuple, %s can be used as a placeholder in the query.
If args is a dict, %(name)s can be used as a placeholder in the query.