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Unable to INSERT into PostgreSQL with psycopg2 python library

I am new to working with SQL and Postgres specifically and am trying to write a simple program that stores a course id and some URLs in an SQL table with two columns. I am using the psycopg2 python library.
I am able to read from the table using:
def get_course_urls(course):
con = open_db_connection()
cur = con.cursor()
query = f"SELECT urls FROM courses WHERE course = '{course}'"
cur.execute(query)
rows = cur.fetchall()
cur.close()
close_db_connection(con)
urls = []
for url in rows:
urls.extend(url[0])
return urls
However, I am unable to insert into the table using:
def format_urls_string(urls):
return '{"' + '","'.join(urls) + '"}'
def add_course_urls(course, urls):
con = open_db_connection()
cur = con.cursor()
query = f"INSERT INTO courses (course, urls) VALUES ('{course}', '{format_urls_string(urls)}');"
print(query)
cur.execute(query)
cur.close()
close_db_connection(con)
add_course_urls("CS136", ["http://google.com", "http://wikipedia.com"])
I do not think anything is wrong with my query because when I run the same query in the SQL Shell it works as I want it to.
The locks on the columns say that the columns are READ-ONLY, however, I am able to insert through the shell. I feel like this is a very minor fix but since I am new to PostgreSQL, I am having some trouble.
Your help is appreciated!

This is the danger of doing the substitution yourself, instead of letting the db connector do it. You looked at your string, yes? You're writing
... VALUES ('CS136', '['http://google.com','http://wikipedia.com']')
which is obviously the wrong syntax. It needs to be
... VALUES ('CS136', '{"http://google.com","http://wikipedia.com"}')
which Python's formatter won't generate. So, you can either format the insertion string by hand, or put placeholders and pass the parameters to the cursor.execute call:
query = "INSERT INTO courses (course, urls) VALUES (%s,%s);"
cur.execute( query, (course, urls) )

"Insert into table values" does not send data

I am new in this and this is my first question. I hope you guys will help.
If my question format is wrong, feel free to comment on that also.
The code is pretty simple. I have DB connection, 2 functions - one for printing and another for choosing how many SQL queries I want to execute and input for those queries.
Idea is to enter a number(INT) of SQL queries - for example, 2 and then in another line user must enter 2 SQL queries.
After that, call_table function will print out current table status/situation/data.
For example - user wants to print out into console table data (table have 2 columns, [name][college], varchar type)
Insert a number of SQL queries you want to execute: 1
Insert SQL statement:
select * from student
('ivan', 'ino')
('nena', 'fer')
('tomislav', 'ino')
('marko', 'fer')
('tomislav', 'ino')
('marko', 'fer')
When I try to insert some values into the same table nothing happens with the table, data is not entered.
The query is 100% correct since I tested it in workbench, also I've tried to create another table from this program and the query was executed normally and the table was created.
I receive no errors.
Code is below:
import pymysql
db = pymysql.connect(host='localhost', user='root', passwd='123456', database='test')
mycursor = db.cursor()
def call_table(data_print):
for i in data_print:
print(i)
def sql_inputs(cursor):
container = []
no = int(input("Insert a number of SQL queries you want to execute: "))
for i in range(no):
container = [input("Insert SQL statement: \n").upper()]
for y in container:
cursor.execute(y)
sql_inputs(mycursor)
call_table(mycursor)
What am I doing wrong?
I tried even more complicated SQL queries but insert into the table is not working.
Thank you

Everything is good with the code, you're just missing cursor.commit()
By default cursor commit is false in python for insert queries.
cursor.execute(y)
cursor.commit()
and if you're done with queries
db.close()

You should append the queries to the container variable
import pymysql
db = pymysql.connect(host='localhost', user='root', passwd='123456', database='test')
mycursor = db.cursor()
def call_table(data_print):
for i in data_print:
print(i)
def sql_inputs(cursor):
container = []
no = int(input("Insert a number of SQL queries you want to execute: "))
for i in range(no):
container.append(input("Insert SQL statement: \n").upper())
for y in container:
cursor.execute(y)
sql_inputs(mycursor)
call_table(mycursor)

At the end of the program, I've added db.commit(), and everything works fine now.
import pymysql
db = pymysql.connect(host='localhost', user='root', passwd='45fa6cb2',
database='ivan')
mycursor = db.cursor()
def call_table(data_print):
for i in data_print:
print(i)
def sql_inputs(cursor):
container = []
no = int(input("Insert a number of SQL queries you want to execute: "))
for i in range(no):
container.append(input("Insert SQL statement: \n").upper())
for y in container:
cursor.execute(y)
sql_inputs(mycursor)
db.commit()
call_table(mycursor)

"No results. Previous SQL was not a query" when trying to query DeltaDNA with Python

I'm currently trying to query a deltadna database. Their Direct SQL Access guide states that any PostgreSQL ODBC compliant tools should be able to connect without issue. Using the guide, I set up an ODBC data source in windows
I have tried adding Set nocount on, changed various formats for the connection string, changed the table name to be (account).(system).(tablename), all to no avail. The simple query works in Excel and I have cross referenced with how Excel formats everything as well, so it is all the more strange that I get the no query problem.
import pyodbc
conn_str = 'DSN=name'
query1 = 'select eventName from table_name limit 5'
conn = pyodbc.connect(conn_str)
conn.setdecoding(pyodbc.SQL_CHAR,encoding='utf-8')
query1_cursor = conn.cursor().execute(query1)
row = query1_cursor.fetchone()
print(row)
Result is ProgrammingError: No results. Previous SQL was not a query.

Try it like this:
import pyodbc
conn_str = 'DSN=name'
query1 = 'select eventName from table_name limit 5'
conn = pyodbc.connect(conn_str)
conn.setdecoding(pyodbc.SQL_CHAR,encoding='utf-8')
query1_cursor = conn.cursor()
query1_cursor.execute(query1)
row = query1_cursor.fetchone()
print(row)
You can't do the cursor declaration and execution in the same row. Since then your query1_cursor variable will point to a cursor object which hasn't executed any query.

Can't get MySQL Connector/Python to Return Dictionary

I have a Python application, in which I'm calling a MySQL stored procedure from my view, like so:
import mysql.connector
proc = 'audit_report'
parms = [data['schoolid'], dateToISO(data['startdatedefault'],'from'), dateToISO(data['enddatedefault'],'to'), joinIntList(data['studypgms'], joinWith), joinIntList(data['fedpgms'], joinWith), joinIntList(data['statuses'], joinWith), data['fullssndefault']]
conn = mysql.connector.connect(user='usr', database='db', password='pwd')
cursor = conn.cursor(dictionary=True)
cursor.callproc(proc, parms)
for result in cursor.stored_results():
print(result.fetchall())
I am getting the data returned as a list of tuples, the standard output. Since I'm using connector version 2.1.7, the docs say adding
dictionary=True
to the cursor declaration should cause the rowset to be returned as a list of dictionaries, with column name as the key of each dictionary. Main difference between my application and the example in the docs is that I'm using cursor.callproc(), whereas the examples use cursor.execute() with actual sql code.
I tried
print(cursor.column_names)
to see if I could get the column names that way, but all I get is
('#_audit_report_arg1', '#_audit_report_arg2', '#_audit_report_arg3', '#_audit_report_arg4', '#_audit_report_arg5', '#_audit_report_arg6', '#_audit_report_arg7')
which looks more like the input parameters to the stored procedure.
Is there any way to actually get the column names of the returned data? The procedure is somewhat complex and contains crosstab-type manipulation, but calling the same stored procedure from MySQL Workbench happily supplies the column names.
Normally, knowing what the output is supposed to be, I could hard-code column names, except this procedure crosstabs the data for the last few columns, and it is unpredictable what they will be until after the query runs.
Thanks...

You can use pymysql in python3 and it should work fine !!
import pymysql.cursors
connection = pymysql.connect(host='',
user='',
password='',
db='test',
charset='utf8mb4',
cursorclass=pymysql.cursors.DictCursor)
try:
with connection.cursor() as cursor:
# Read a single record
sql = "query"
cursor.execute(sql)
result = cursor.fetchone()
num_fields = len(cursor.description)
field_names = [i[0] for i in cursor.description]
print (field_names)
finally:
connection.close()

Python PYODBC - Previous SQL was not a query

I have the following python code, it reads through a text file line by line and takes characters x to y of each line as the variable "Contract".
import os
import pyodbc
cnxn = pyodbc.connect(r'DRIVER={SQL Server};CENSORED;Trusted_Connection=yes;')
cursor = cnxn.cursor()
claimsfile = open('claims.txt','r')
for line in claimsfile:
#ldata = claimsfile.readline()
contract = line[18:26]
print(contract)
cursor.execute("USE calms SELECT XREF_PLAN_CODE FROM calms_schema.APP_QUOTE WHERE APPLICATION_ID = "+str(contract))
print(cursor.fetchall())
When including the line cursor.fetchall(), the following error is returned:
Programming Error: Previous SQL was not a query.
The query runs in SSMS and replace str(contract) with the actual value of the variable results will be returned as expected.
Based on the data, the query will return one value as a result formatted as NVARCHAR(4).
Most other examples have variables declared prior to the loop and the proposed solution is to set NO COUNT on, this does not apply to my problem so I am slightly lost.
P.S. I have also put the query in its own standalone file without the loop to iterate through the file in case this was causing the problem without success.

In your SQL query, you are actually making two commands: USE and SELECT and the cursor is not set up with multiple statements. Plus, with database connections, you should be selecting the database schema in the connection string (i.e., DATABASE argument), so TSQL's USE is not needed.
Consider the following adjustment with parameterization where APPLICATION_ID is assumed to be integer type. Add credentials as needed:
constr = 'DRIVER={SQL Server};SERVER=CENSORED;Trusted_Connection=yes;' \
'DATABASE=calms;UID=username;PWD=password'
cnxn = pyodbc.connect(constr)
cur = cnxn.cursor()
with open('claims.txt','r') as f:
for line in f:
contract = line[18:26]
print(contract)
# EXECUTE QUERY
cur.execute("SELECT XREF_PLAN_CODE FROM APP_QUOTE WHERE APPLICATION_ID = ?",
[int(contract)])
# FETCH ROWS ITERATIVELY
for row in cur.fetchall():
print(row)
cur.close()
cnxn.close()