ValueError: Could not process parameters in Python/MySQL
Question:
I want to prevent duplicate usernames when people register.
Here is my code snippet:
def submit(self):
username_info = username.get()
username_password = password.get()
#connect to db
db = mysql.connector.connect(host = 'localhost', user = 'root', password = '', database = 'user')
#create a cursor
mycursor = db.cursor()
#insert to db
sql = ("INSERT INTO useraccess (user_type, password) VALUES (%s, %s)")
query = (username_info, username_password)
mycursor.execute(sql, query)
#commit
db.commit()
#create a messagebox
messagebox.showinfo("Registration", "Successfully Register")
#if username has been used
find_user = ("SELECT * FROM useraccess WHERE user_type = ?")
user_query = (username_info)
mycursor.execute(find_user, user_query)
#if (username == username_info):
if mycursor.fetchall():
messagebox.showerror("Registration", "The username chosen is already used. Please select another username")
else:
messagebox.showinfo("Registration", "Account Created!")
But every time I run it, although the username has been registered in the db, it only shows the successfully created messagebox and error:
ValueError: Could not process parameters.
Anyone can help me to solve this problem?
Answers:
I believe the source of the problem is in the line
user_query = (username_info)
It should be
user_query = (username_info,)
The trailing comma is the syntactic difference between an expression in parentheses and a tuple.
Another issue with code is the query:
find_user = ("SELECT * FROM useraccess WHERE user_type = ?")
Which should be:
find_user = ("SELECT * FROM useraccess WHERE user_type = %s")
Have you checked these variables,
username_info = username.get()
username_password = password.get()
are they in proccesable formats? (i.e. can you directly put the username.get() into user_type ?)
I’m not familiar with this way of passing a parameter
find_user = ("SELECT * FROM useraccess WHERE user_type = ?")
have you double checked this? (why not the %s method?)
also, you probably get the “Account Created!” because mycursor.fetchall() fails.
I want to prevent duplicate usernames when people register.
Here is my code snippet:
def submit(self):
username_info = username.get()
username_password = password.get()
#connect to db
db = mysql.connector.connect(host = 'localhost', user = 'root', password = '', database = 'user')
#create a cursor
mycursor = db.cursor()
#insert to db
sql = ("INSERT INTO useraccess (user_type, password) VALUES (%s, %s)")
query = (username_info, username_password)
mycursor.execute(sql, query)
#commit
db.commit()
#create a messagebox
messagebox.showinfo("Registration", "Successfully Register")
#if username has been used
find_user = ("SELECT * FROM useraccess WHERE user_type = ?")
user_query = (username_info)
mycursor.execute(find_user, user_query)
#if (username == username_info):
if mycursor.fetchall():
messagebox.showerror("Registration", "The username chosen is already used. Please select another username")
else:
messagebox.showinfo("Registration", "Account Created!")
But every time I run it, although the username has been registered in the db, it only shows the successfully created messagebox and error:
ValueError: Could not process parameters.
Anyone can help me to solve this problem?
I believe the source of the problem is in the line
user_query = (username_info)
It should be
user_query = (username_info,)
The trailing comma is the syntactic difference between an expression in parentheses and a tuple.
Another issue with code is the query:
find_user = ("SELECT * FROM useraccess WHERE user_type = ?")
Which should be:
find_user = ("SELECT * FROM useraccess WHERE user_type = %s")
Have you checked these variables,
username_info = username.get()
username_password = password.get()
are they in proccesable formats? (i.e. can you directly put the username.get() into user_type ?)
I’m not familiar with this way of passing a parameter
find_user = ("SELECT * FROM useraccess WHERE user_type = ?")
have you double checked this? (why not the %s method?)
also, you probably get the “Account Created!” because mycursor.fetchall() fails.