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Why am I getting "mysql.connector.errors.InternalError: Unread result found" when I submit my select options form in index.html [duplicate]

I am inserting JSON data into a MySQL database
I am parsing the JSON and then inserting it into a MySQL db using the python connector
Through trial, I can see the error is associated with this piece of code
for steps in result['routes'][0]['legs'][0]['steps']:
query = ('SELECT leg_no FROM leg_data WHERE travel_mode = %s AND Orig_lat = %s AND Orig_lng = %s AND Dest_lat = %s AND Dest_lng = %s AND time_stamp = %s')
if steps['travel_mode'] == "pub_tran":
travel_mode = steps['travel_mode']
Orig_lat = steps['var_1']['dep']['lat']
Orig_lng = steps['var_1']['dep']['lng']
Dest_lat = steps['var_1']['arr']['lat']
Dest_lng = steps['var_1']['arr']['lng']
time_stamp = leg['_sent_time_stamp']
if steps['travel_mode'] =="a_pied":
query = ('SELECT leg_no FROM leg_data WHERE travel_mode = %s AND Orig_lat = %s AND Orig_lng = %s AND Dest_lat = %s AND Dest_lng = %s AND time_stamp = %s')
travel_mode = steps['travel_mode']
Orig_lat = steps['var_2']['lat']
Orig_lng = steps['var_2']['lng']
Dest_lat = steps['var_2']['lat']
Dest_lng = steps['var_2']['lng']
time_stamp = leg['_sent_time_stamp']
cursor.execute(query,(travel_mode, Orig_lat, Orig_lng, Dest_lat, Dest_lng, time_stamp))
leg_no = cursor.fetchone()[0]
print(leg_no)
I have inserted higher level details and am now searching the database to associate this lower level information with its parent. The only way to find this unique value is to search via the origin and destination coordinates with the time_stamp. I believe the logic is sound and by printing the leg_no immediately after this section, I can see values which appear at first inspection to be correct
However, when added to the rest of the code, it causes subsequent sections where more data is inserted using the cursor to fail with this error -
raise errors.InternalError("Unread result found.")
mysql.connector.errors.InternalError: Unread result found.
The issue seems similar to MySQL Unread Result with Python
Is the query too complex and needs splitting or is there another issue?
If the query is indeed too complex, can anyone advise how best to split this?
EDIT As per #Gord's help, Ive tried to dump any unread results
cursor.execute(query,(leg_travel_mode, leg_Orig_lat, leg_Orig_lng, leg_Dest_lat, leg_Dest_lng))
leg_no = cursor.fetchone()[0]
try:
cursor.fetchall()
except mysql.connector.errors.InterfaceError as ie:
if ie.msg == 'No result set to fetch from.':
pass
else:
raise
cursor.execute(query,(leg_travel_mode, leg_Orig_lat, leg_Orig_lng, leg_Dest_lat, leg_Dest_lng, time_stamp))
But, I still get
raise errors.InternalError("Unread result found.")
mysql.connector.errors.InternalError: Unread result found.
[Finished in 3.3s with exit code 1]
scratches head
EDIT 2 - when I print the ie.msg, I get -
No result set to fetch from

All that was required was for buffered to be set to true!
cursor = cnx.cursor(buffered=True)
The reason is that without a buffered cursor, the results are "lazily" loaded, meaning that "fetchone" actually only fetches one row from the full result set of the query. When you will use the same cursor again, it will complain that you still have n-1 results (where n is the result set amount) waiting to be fetched. However, when you use a buffered cursor the connector fetches ALL rows behind the scenes and you just take one from the connector so the mysql db won't complain.

I was able to recreate your issue. MySQL Connector/Python apparently doesn't like it if you retrieve multiple rows and don't fetch them all before closing the cursor or using it to retrieve some other stuff. For example
import mysql.connector
cnxn = mysql.connector.connect(
host='127.0.0.1',
user='root',
password='whatever',
database='mydb')
crsr = cnxn.cursor()
crsr.execute("DROP TABLE IF EXISTS pytest")
crsr.execute("""
CREATE TABLE pytest (
id INT(11) NOT NULL AUTO_INCREMENT,
firstname VARCHAR(20),
PRIMARY KEY (id)
)
""")
crsr.execute("INSERT INTO pytest (firstname) VALUES ('Gord')")
crsr.execute("INSERT INTO pytest (firstname) VALUES ('Anne')")
cnxn.commit()
crsr.execute("SELECT firstname FROM pytest")
fname = crsr.fetchone()[0]
print(fname)
crsr.execute("SELECT firstname FROM pytest") # InternalError: Unread result found.
If you only expect (or care about) one row then you can put a LIMIT on your query
crsr.execute("SELECT firstname FROM pytest LIMIT 0, 1")
fname = crsr.fetchone()[0]
print(fname)
crsr.execute("SELECT firstname FROM pytest") # OK now
or you can use fetchall() to get rid of any unread results after you have finished working with the rows you retrieved.
crsr.execute("SELECT firstname FROM pytest")
fname = crsr.fetchone()[0]
print(fname)
try:
crsr.fetchall() # fetch (and discard) remaining rows
except mysql.connector.errors.InterfaceError as ie:
if ie.msg == 'No result set to fetch from.':
# no problem, we were just at the end of the result set
pass
else:
raise
crsr.execute("SELECT firstname FROM pytest") # OK now

cursor.reset() is really what you want.
fetchall() is not good because you may end up moving unnecessary data from the database to your client.

The problem is about the buffer, maybe you disconnected from the previous MySQL connection and now it cannot perform the next statement. There are two ways to give the buffer to the cursor. First, only to the particular cursor using the following command:
import mysql.connector
cnx = mysql.connector.connect()
# Only this particular cursor will buffer results
cursor = cnx.cursor(buffered=True)
Alternatively, you could enable buffer for any cursor you use:
import mysql.connector
# All cursors created from cnx2 will be buffered by default
cnx2 = mysql.connector.connect(buffered=True)
cursor = cnx.cursor()
In case you disconnected from MySQL, the latter works for you.
Enjoy coding

If you want to get only one result from a request, and want after to reuse the same connexion for other requests, limit your sql select request to 1 using "limit 1" at the end of your request.
ex "Select field from table where x=1 limit 1;"
This method is faster using "buffered=True"

Set the consume_results argument on the connect() method to True.
cnx = mysql.connector.connect(
host="localhost",
user="user",
password="password",
database="database",
consume_results=True
)
Now instead of throwing an exception, it basically does fetchall().
Unfortunately this still makes it slow, if you have a lot of unread rows.

There is also a possibility that your connection to MySQL Workbench is disconnected. Establish the connection again. This solved the problem for me.

cursor.reset()
and then create tables and load entries

Would setting the cursor within the for loop, executing it, and then closing it again in the loop help?
Like:
for steps in result['routes'][0]['legs'][0]['steps']:
cursor = cnx.cursor()
....
leg_no = cursor.fetchone()[0]
cursor.close()
print(leg_no)

Print Data from MySQL Database to Console from Python

I'm using Visual Studio 2017 with a Python Console environment. I have a MySQL database set up which I can connect to successfully. I can also Insert data into the DB. Now I'm trying to display/fetch data from it.
I connect fine, and it seems I'm fetching data from my database, but nothing is actually printing to the console. I want to be able to fetch and display data, but nothing is displaying at all.
How do I actually display the data I select?
#importing module Like Namespace in .Net
import pypyodbc
#creating connection Object which will contain SQL Server Connection
connection = pypyodbc.connect('Driver={SQL Server};Server=DESKTOP-NJR6F8V\SQLEXPRESS;Data Source=DESKTOP-NJR6F8V\SQLEXPRESS;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=True;ApplicationIntent=ReadWrite;MultiSubnetFailover=False')
cursor = connection.cursor()
SQLCommand = ("SELECT ID FROM MyAI_DB.dbo.WordDefinitions WHERE ID > 117000")
#Processing Query
cursor.execute(SQLCommand)
#Commiting any pending transaction to the database.
connection.commit()
#closing connection
#connection.close()

I figured it out. I failed to include the right Print statement. Which was:
print(cursor.fetchone())
I also had the connection.commit statement in the wrong place (it was inserted even executing the Print statement). The final code that worked was this:
#importing module Like Namespace in .Net
import pypyodbc
#creating connection Object which will contain SQL Server Connection
connection = pypyodbc.connect('Driver={SQL Server};Server=DESKTOP-NJR6F8V\SQLEXPRESS;Data Source=DESKTOP-NJR6F8V\SQLEXPRESS;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=True;ApplicationIntent=ReadWrite;MultiSubnetFailover=False')
cursor = connection.cursor()
SQLCommand = ("SELECT * FROM MyAI_DB.dbo.WordDefinitions")
#Processing Query
cursor.execute(SQLCommand)
#Commiting any pending transaction to the database.
print(cursor.fetchone())
connection.commit()
#closing connection
#connection.close()

python-mysql cursor.execute failing with access denied error

I have two machines: local_machine, server_machine. I have mysql server on server_machine and sftp server on local_machine. I am trying to send sritest.csv file (UTF-8) from local_machine to server_machine using python. These are the contents of sritest.csv:
1,2,3
I have the sql query saved in sritest.sql and these are the contents of the file:
LOAD DATA INFILE '{}'
INTO TABLE TESTBED_STAGING.test
COLUMNS TERMINATED BY ','
;
This is the python script I have now:
import MySQLdb
import os
import string
# Open database connection
db = MySQLdb.connect (host="1.2.3.4",port=3306,user="app_1",\
passwd="passwd",db="TESTBED_STAGING")
cursor=db.cursor()
#Query under testing
sql = open('sritest.sql','r').read()
print sql
l = os.listdir(".")
for file_name in l:
if file_name.endswith('sritest.csv'):
print 'the csv file we are reading is: '+file_name
#try:
cursor = db.cursor()
print 'filename is '+sql.format(file_name)
cursor.execute(sql.format(file_name))
db.commit()
'''
except Exception:
# Rollback in case there is any error
db.rollback()
print 'ERROR - So, rollback :( :( '
'''
# disconnect from server
db.close()
In the above script, I commented try,except so I can see the error where it breaks. Currently the code is breaking at cursor.execute(sql.format(file_name)) line with this error:
OperationalError: (1045, "Access denied for user 'app_1'#'%' (using password: YES)")
I have been playing around but not able to fix it. Any suggestions/ideas?

For starters, creating cursor at every loop is not a good idea. You've already created a cursor earlier, so you can remove the cursor declaration in the for loop.
Second, I think your error is due to lack of access on MySQL server at 1.2.3.4 remotely using user app_1. Try this on the server's MySQL console,
GRANT ALL PRIVILEGES ON TESTBED_STAGING.* TO 'app_1'#'%';
Lastly, try and avoid using print "line" notation and start switching to the print("line") notation for compatibility with Python 3.x

I figured out the answer and decided to leave this question open for those who might face the similar problem:
In the MySQL server (server_machine), make sure you do this after you start mysql:
mysql>grant all privileges on *.* to 'app_1'#'%' identified by 'passwd';
change LOAD DATA INFILE '{}' in sritest.sql to LOAD DATA LOCAL INFILE '{}'
In the python code, edit the MySQLdb.connect statement as:
db = MySQLdb.connect (host="1.2.3.4",port=3306,user="app_1",\
passwd="passwd",db="TESTBED_STAGING", local_infile=1)
All errors are eliminated and data is transferred.

Empty table in MySQL even though Python can insert data into table

I'm new to mySQL and Python.
I have code to insert data from Python into mySQL,
conn = MySQLdb.connect(host="localhost", user="root", passwd="kokoblack", db="mydb")
for i in range(0,len(allnames)):
try:
query = "INSERT INTO resumes (applicant, jobtitle, lastworkdate, lastupdate, url) values ("
query = query + "'"+allnames[i]+"'," +"'"+alltitles[i]+"',"+ "'"+alldates[i]+"'," + "'"+allupdates[i]+"'," + "'"+alllinks[i]+"')"
x = conn.cursor()
x.execute(query)
row = x.fetchall()
except:
print "error"
It seems to be working fine, because "error" never appears. Instead, many rows of "1L" appear in my Python shell. However, when I go to MySQL, the "resumes" table in "mydb" remains completely empty.
I have no idea what could be wrong, could it be that I am not connected to MySQL's server properly when I'm viewing the table in MySQL? Help please.
(I only use import MySQLdb, is that enough?)

use commit to commit the changes that you have done
MySQLdb has autocommit off by default, which may be confusing at first
You could do commit like this
conn.commit()
or
conn.autocommit(True) Right after the connection is created with the DB

why cx_Oracle and sqlplus give different results for the same select query

By using Python and cx_Oracle, I am trying to insert rows to a table.
con = cx_Oracle.connect(ORACLE_USER+'/'+PASS+'#'+TNS)
cursor = con.cursor()
...
try:
cursor.executemany("INSERT INTO table(ID,NAME) VALUES(...)"
except cx_Oracle,exc:
error ,=exc.args
print error.code
print error.message
cursor.close()
con.close()
After insert all the rows from an input file, by using select query in cx_Oracle, I can see the inserted rows. However, sqlplus gives no results when I enter "select * from table;"
Is there something that I missed about cx_Oracle or is there a buffer in oracle client that shows the old results with sqlplus when it is connected to a remote db?

Have you committed your insert?
con.commit() #after inserts
or
con.autocommit = true #before inserts

I had an inverted problem: I added rows using sqlquery and after 2 hours of suffering read this post and guess, that I should close my session. I closed the console and managed to get my data!