Why is my Python MySQL update code not working? - mysql

Question

I'm trying to make a form in which my user can update their login username (info is in a MySQL database) but I get this error when I run the code and enter test values:
Error Dui to : 1064 (42000): 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 '%s WHERE client_ID = '0001'' at line 1
I desperately need help. This the code
old_uname = StringVar()
new_name = StringVar()
def update_uname():
if old_uname.get()==" " or new_name.get()==" ":
messagebox.showerror("Error" , "All Fields Are Required" , parent = wintask)
else:
try:
con = mysql.connector.connect(host="<>", user="<>", password="<>",database="<>")
cur = con.cursor()
update_command = "UPDATE login_information SET username = %s WHERE client_ID = '0001'"
val = (new_name.get())
cur.execute(update_command, val)
con.commit()
messagebox.showinfo("Success", "Username has been updated!", parent=wintask)
except Exception as es:
messagebox.showerror("Error" , f"Error Dui to : {str(es)}", parent = wintask)
PS: I have no trouble w the SQL connection. I'm fairly new to coding

Answer 1

I referred to the documentation https://dev.mysql.com/doc/connector-python/en/connector-python-api-mysqlcursor-execute.html
and I think the following is relevant to you:
The parameters found in the tuple or dictionary params are bound to the variables in the operation.
and then the Note:
In Python, a tuple containing a single value must include a comma. For example, ('abc') is evaluated as a scalar while ('abc',) is evaluated as a tuple.
Your code:
new_name = StringVar()
....
val = (new_name.get())
cur.execute(update_command, val)
So the parameter params is a string:
>>> a="test"
>>> (a)
'test'
>>> b=(a)
>>> type(b)
<class 'str'>
>>> c=(a,)
>>> type(c)
<class 'tuple'>
let you try cur.execute(update_command, (val,)) # the comma after val