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I'm using python, and I work with SELECT and UPDATE statement in a single cursor for the same table

Here is the code that I try to run
connection = mysql.connector.connect(host='host',
database="database",
user="user",
password="password")
cursor = connection.cursor()
cursor.execute("SELECT * FROM employee WHERE admin = 'true'")
dict_result = cursor.fetchone()
while dict_result is not None:
print(dict_result)
cursor.execute("UPDATE employee SET salary = 10000 WHERE uuid = '%s'" % (dict_result[0]))
dict_result = cursor.fetchone()
connection.close()
Error achieved by above:
But i got 'unread result found' error

I had a similar error where i had to commit after the fetch to make sure that all of the results was gathered as the fetch call is asynchronous.
My fix was to add:
connection.commit()
After the fetch but before the close.
Ex:
connection = mysql.connector.connect(host='host',
database="database",
user="user",
password="password")
cursor = connection.cursor()
cursor.execute("SELECT * FROM employee WHERE admin = 'true'")
dict_result = cursor.fetchone()
while dict_result is not None:
print(dict_result)
cursor.execute("UPDATE employee SET salary = 10000 WHERE uuid = '%s'" % (dict_result[0]))
dict_result = cursor.fetchone()
connection.commit()
connection.close()

Mysql table name getting unwanted quotes resulting table does not exist error

import mysql.connector
def add_features_to_db(stockname, timeframe, date, feature):
try:
conn = mysql.connector.connect(
user='root', password='', host='localhost', database='fx003')
cursor = conn.cursor()
dbtable = stockname + timeframe
mySql_insert_query = """INSERT INTO `%s` (date, trend) VALUES ( `%s`, `%s` )"""
record = (dbtable, date, feature)
cursor.execute(mySql_insert_query, record)
conn.commit()
print("Record inserted successfully")
except mysql.connector.Error as error:
print("Failed to insert into MySQL table {}".format(error))
finally:
if conn.is_connected():
cursor.close()
conn.close()
print("MySQL connection is closed")
add_features_to_db("aud-cad", "_30mins", "2021-09-24 21:00:00", "Short")
I have the code above and giving me the below error:
Failed to insert into MySQL table 1146 (42S02): Table 'fx003.'aud-cad_30mins'' doesn't exist
aud-cad_30mins table does exist and an insert query like below doing its job:
mySql_insert_query = """INSERT INTO aud-cad_30mins (date, trend) VALUES ( "2021-09-24 21:00:00","Short" )"""
So when I try to use variables in the query, it gives the error. Why the table name getting unwanted quotes? Checked several tutorials but couldn't find a solution, any ideas?

The table name should be hardcoded in the query string instead of having it there as a placeholder %s, which is meant for the values to be inserted. So if you have the table name in the variable, you can replace it via format() before calling cursor.execute()
dbtable = stockname + timeframe
mySql_insert_query = """INSERT INTO {} (date, trend) VALUES ( %s, %s )""".format(dbtable)
see the examples in the docs
edit: as Bill mentioned in the comment, dont add the backticks around the %s placeholders.

Failed to insert user input into MySQL database

I have created a database and inserted some value using python manual code but when i tried to taking input from user then inserting that input to my database table,i failed as i tried many ways.
Here is my code
import mysql.connector
mydb = mysql.connector.connect(
host="localhost",
user="root",
passwd="Adee11ruchi#",
database="hdatabase"
)
mycursor = mydb.cursor()
name= str(input("What is your first name? "))
address=str(input("enter address:"))
#mycursor.execute("CREATE TABLE customers (name VARCHAR(255), address VARCHAR(255))")
mycursor.execute = ("""INSERT INTO customers (name, address) VALUES (r{}, r{})""".format(name, address))
#val = ('Peter', 'Lowstreet 4')
mydb.commit()
print(mycursor.rowcount, "record inserted.")
It showing me as
What is your first name? diyu
enter address:hiouy
-1 record inserted.
What is the issue,i failed to find out.

You should be using a prepared statement here. Consider this version:
mycursor = mydb.cursor(prepared=True)
name = input("What is your first name? ")
address = input("enter address:")
sql = "INSERT INTO customers (name, address) VALUES (%s, %s)"
mycursor.execute = (sql, (name, address,))
mydb.commit()
The main takeaways points here are that you leave the values to be bound as parameters %s, and then you bind the values as a tuple in the call to cursor#execute. Note that the prepared statement API will handle the proper formatting of the inputs for you.

python: update mysql table

I am trying to update a mysql table with variable names. Below is the code that is not working for me:
import mysql.connector
conn= mysql.connector.connect(
host=host,
user=user,
passwd=password,
database=database
)
cur = conn.cursor()
cur.execute("update player_list set country = '%s', region = '%s',name = '%s' where id = %s "
% (country, region,name, id))
Running the "cur execute" line returns the following error:
mysql.connector.errors.InternalError: Unread result found
The ID column is an integer if it has any importance.

I don't see any code here how you've created your cursor, but looks like you need to specify buffered mode for your sql class to read.
Please, refer to official documentation and change your code to use buffer=True while creating your cursor and use it afterwards.
https://dev.mysql.com/doc/connector-python/en/connector-python-api-mysqlcursorbuffered.html

Try
with conn.cursor() as cur:
sql = "update player_list set country = '%s', region = '%s',name = '%s' where id = %s" % (country, region,name, id)
cur.execute(sql)
conn.commit()
and add buffered = True into your conn like
connection = mysql.connector.connect([...], buffered = True)

How can I format strings to query with mysqldb in Python?

How do I do this correctly:
I want to do a query like this:
query = """SELECT * FROM sometable
order by %s %s
limit %s, %s;"""
conn = app_globals.pool.connection()
cur = conn.cursor()
cur.execute(query, (sortname, sortorder, limit1, limit2) )
results = cur.fetchall()
All works fine but the order by %s %s is not putting the strings in correctly. It is putting the two substitutions in with quotes around them.
So it ends up like:
ORDER BY 'somecol' 'DESC'
Which is wrong should be:
ORDER BY somecol DESC
Any help greatly appreciated!

paramstyle
Parameter placeholders can only be used to insert column values. They can not be used for other parts of SQL, such as table names, statements, etc.

%s placeholders inside query string are reserved for parameters. %s in 'order by %s %s' are not parameters. You should make query string in 2 steps:
query = """SELECT * FROM sometable order by %s %s limit %%s, %%s;"""
query = query % ('somecol', 'DESC')
conn = app_globals.pool.connection()
cur = conn.cursor()
cur.execute(query, (limit1, limit2) )
results = cur.fetchall()
DO NOT FORGET to filter first substitution to prevent SQL-injection possibilities

Not all parts of an SQL query can be parametrized. The DESC keyword for example is not
a parameter. Try
query = """SELECT * FROM sometable
order by %s """ + sortorder + """
limit %s, %s"""
cur.execute(query, (sortname, limit1, limit2) )

You could try this alternatively...
query = """SELECT * FROM sometable
order by {0} {1}
limit {2}, {3};"""
sortname = 'somecol'
sortorder = 'DESC'
limit1 = 'limit1'
limit2 = 'limit2'
print(query.format(sortname, sortorder, limit1, limit2))