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sqlite3 python query needed for quiz isn't working

For my school project I decided to make a physics revision tool. The tool lets users log in and saves information about their performance on certain questions. As a result of this I realised I needed to name each table used to store each individual users scores so I thought using .format would be appropriate. It seemed to be working fine until the point where i needed to add code that would add information to the table. From the testing i have done on the code so far, i think the problem is because i am using .format it won't actually create any columns. I don't know how to get around that please help. Appropriate sections of code have been provided:
def quesprep():
intro.destroy()
con= sqlite3.connect("login.db")
c= con.cursor()
c.execute("SELECT accid FROM credentials WHERE accountname = ?", (user,))
global results
results=c.fetchall()
con.commit()
con.close()
con= sqlite3.connect("store.db")
c= con.cursor()
c.execute("""CREATE TABLE IF NOT EXISTS {}(mod integer, ques integer,score integer)""".format(results))
c.execute("INSERT INTO {} Values(mod=2,ques=1, score=0)".format(results))
con.commit()
con.close()
ques()
def mod2q1page():
questionspage.destroy()
con= sqlite3.connect("login.db")
c= con.cursor()
c.execute("SELECT accid FROM credentials WHERE accountname = ?", (user,))
global results
results=c.fetchall()
con.commit()
con= sqlite3.connect("store.db")
c= con.cursor()
c.execute("INSERT OR IGNORE INTO {} VALUES(mod=2, ques=2, score=0)" .format(results))

There seems to be several things wrong here.
Format takes a variable inside the {} ... like {0}, {1} etc
Placeholders are the preferred route to take with formatting sql queries ... like you did in your SELECT
I am not sure what the issue is here but if you are trying to add columns, you need to ALTER the table ... not INSERT. INSERT will add a row item. If you can post the error, perhaps we can help a little more. To start you out though, try placeholders in lieu of format.
Also, fetchall returns a list of tuples ... need to send a tuple in sql, not a list.
for x in results:
c.execute("INSERT INTO ? (col1, col2, col3) VALUES (1, 2, 3);", x)
Edit:
I stand corrected - I ran this code:
data = [('user',)]
cursor.execute("INSERT INTO ? (id, email, password) VALUES (1, test, test);", data)
syntax error because you cannot add placeholder to table name. Read here
I used format with the {0}:
cursor.execute("INSERT INTO {0} (id, email, password) VALUES (1, test, test);".format('user'))
The query was successful. I believe that is your problem here.

found a solution:
intro.destroy()
con= sqlite3.connect("login.db")
c= con.cursor()
c.execute("SELECT accountname FROM credentials WHERE accountname = ?", (user,))
results=c.fetchone()
global tablename
tablename=" ".join(map(str, (results)))
con.commit()
con.close()
global m
m="mod"
global q
q="ques"
global s
s="score"
fieldtype="INTEGER"
con=sqlite3.connect("store.db")
c=con.cursor()
c.execute('CREATE TABLE IF NOT EXISTS {} ({fc} {ft}, {sc} {ft2}, {tc} {ft3})'\
.format(tablename, fc=m, ft=fieldtype, sc=q, ft2=fieldtype, tc=s,
ft3=fieldtype))
con.commit()
con.close()

retrieving data from table based on a value from a python variable

I am writing a function that will retrieve data from sqlite table based on the parameters user provide. This is the function so far
def database_retrieve(db_file, id):
try:
conn = sqlite3.connect(db_file)
with conn:
sql_command = "SELECT * FROM my_table WHERE id = "+id
cur = conn.cursor()
cur.execute(sql_command)
result = cur.fetchall()
return result
except Exception as e:
print(e)
db_file = 'testdb.db'
print(database_retrieve(db_file, 'subject1'))
This gives me the following error
no such column: subject1
None
When I add subject1, which is an entry under the id column in my_table, directly to the sql command like this
sql_command = "SELECT * FROM my_table WHERE id = 'subject1'"
it works fine and prints all the data.
I am new to sqlite3. Please help. Thanks in advance
These are the links I used to come this far
Python sqlite3 string variable in execute
https://www.dummies.com/programming/databases/how-to-retrieve-data-from-specific-rows-in-mysql-databases/

When you do this
sql_command = "SELECT * FROM my_table WHERE id = "+id
The value of sql_command is
"SELECT * FROM my_table WHERE id = subject1"
As you can see, subject1 is not in quotes. sqlite thinks it is a column, that's why you see that error.
Instead, do this
sql_command = "SELECT * FROM my_table WHERE id = ?"
cur.execute(sql_command, [id])
? acts as a placeholder for the variable id.
The official sqlite3 documentation mentions few others methods
https://docs.python.org/2/library/sqlite3.html

The sql_command string being generated should be something like this (Formatted string):
sql_command = "SELECT * FROM my_table WHERE id = %s AND name = %s" % (212212, 'shashank')

Use output of one SQL query in another SQL query in Python

I am working with a SQL Database on Python. After making the connection, I want to use the output of one query in another query.
Example: query1 gives me a list of all tables in a schema. I want to use each table name from query1 in my query2.
query2 = "SELECT TOP 200 * FROM db.schema.table ORDER BY ID"
I want to use this query for each of the table in the output of query1.
Can someone help me with the Python code for it?

Here is a working example on how to do what you are looking to do. I didn't look up the schemes for the tablelist, but you can simply substitute the SQL code to do so. I just 'faked it' by unioning a statement of 2 tables. There are plenty of other answer on that SQL code and I don't want to clutter this answer:
How do I get list of all tables in a database using TSQL?
It looks like the key part you may have been missing was the join step to build the second SQL statement. This should be enough of a starting point to craft exactly what you are looking for.
import pypyodbc
def main():
table_list = get_table_list()
for table in table_list:
print_table(table)
def print_table(table):
thesql = " ".join(["SELECT TOP 10 businessentityid FROM", table])
connection = get_connection()
cursor = connection.cursor()
cursor.execute(thesql)
for row in cursor:
print (row["businessentityid"])
cursor.close()
connection.close()
def get_table_list():
table_list = []
thesql = ("""
SELECT 'Sales.SalesPerson' AS thetable
UNION
SELECT 'Person.BusinessEntity' thetable
""")
connection = get_connection()
cursor = connection.cursor()
cursor.execute(thesql)
for row in cursor:
table_list.append(row["thetable"])
cursor.close()
connection.close()
return table_list
def get_connection():
'''setup connection depending on which db we are going to write to in which environment'''
connection = pypyodbc.connect(
"Driver={SQL Server};"
"Server=YOURSERVER;"
"Database=AdventureWorks2014;"
"Trusted_Connection=yes"
)
return connection
main ()

creating a table in sqlite3 python

I apologize in advance for asking such a basic question but I am new to SQlite3 and having trouble starting. I am trying to build a database with one table. I used the following code to build a table.
import sqlite3
conn = sqlite3.connect('example.db')
c = conn.cursor()
c.execute('''CREATE TABLE mytable
(start, end, score)''')
but whenever I try to update or access the table it seems that it doesnt exist or maybe it exists in a different database. I also tried creating a table called example.mytable but I got the error:
sqlite3.OperationalError: unknown database example
What am I missing?
Thanks

I think that a commit is needed after inserts (schema changes such as new tables should automatically commit). I would suggest adding the full path to your database as well to make sure you are accessing the same location next time round.
Here is an extension on your code:
import sqlite3
def create():
try:
c.execute("""CREATE TABLE mytable
(start, end, score)""")
except:
pass
def insert():
c.execute("""INSERT INTO mytable (start, end, score)
values(1, 99, 123)""")
def select(verbose=True):
sql = "SELECT * FROM mytable"
recs = c.execute(sql)
if verbose:
for row in recs:
print row
db_path = r'C:\Users\Prosserc\Documents\Geocoding\test.db'
conn = sqlite3.connect(db_path)
c = conn.cursor()
create()
insert()
conn.commit() #commit needed
select()
c.close()
Output:
(1, 99, 123)
After closing the program if I log onto the SQLite database the data is still there.

import sqlite3;
import pandas as pd;
con=None
def getConnection():
databaseFile="./test.db"
global con
if con == None:
con=sqlite3.connect(databaseFile)
return con
def createTable(con):
try:
c = con.cursor()
c.execute("""CREATE TABLE IF NOT EXISTS Movie
(start, end, score)""")
except Exception as e:
pass
def insert(con):
c = con.cursor()
c.execute("""INSERT INTO Movie (start, end, score)
values(1, 99, 123)""")
def queryExec():
con=getConnection()
createTable(con)
insert(con)
# r = con.execute("""SELECT * FROM Movie""")
result=pd.read_sql_query("select * from Movie;",con)
return result
r = queryExec()
print(r)

How to check with python if a table is empty?

Using python and MySQLdb, how can I check if there are any records in a mysql table (innodb)?

Just select a single row. If you get nothing back, it's empty! (Example from the MySQLdb site)
import MySQLdb
db = MySQLdb.connect(passwd="moonpie", db="thangs")
results = db.query("""SELECT * from mytable limit 1""")
if not results:
print "This table is empty!"

Something like
import MySQLdb
db = MySQLdb.connect("host", "user", "password", "dbname")
cursor = db.cursor()
sql = """SELECT count(*) as tot FROM simpletable"""
cursor.execute(sql)
data = cursor.fetchone()
db.close()
print data
will print the number or records in the simpletable table.
You can then test if to see if it is bigger than zero.