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Creating a table based on input, if input doesnt exist in db file creates a table, if exists, writes ID to it

I'm trying to make a program in Python that requests an input and if the table in the DB exists, writes to it, and if it doesn't, creates it.
Here is the existing code:
connection = sqlite3.connect('AnimeScheduleSub.db')
cursor = connection.cursor()
anime_id = input('enter server id')
discord_user_id = int(input('Enter token'))
try:
cursor.execute("SELECT * FROM {}".format(anime_id))
results = cursor.fetchall()
print(results)
except:
command1 = f"""CREATE TABLE IF NOT EXISTS
{anime_id}(discord_user_id INTEGER)"""
cursor.execute(command1)
Basically, what it's doing (or what I'm trying to achieve) is the try loop is meant to check if the anime_id table exists. The except loop is meant to create the table if the try loop failed.
But it doesn't work, and I have no idea why. Any help would be much appreciated.

command1 = f"""CREATE TABLE IF NOT EXISTS
A{anime_id}(discord_user_id INTEGER)"""
Creating table name with just numbers are not supported by sql.
You should start with a letter and then use numbers.

You should "ask" the DB if the table is there or not.
Something like the below.
anime_id = input('enter server id')
SELECT name FROM sqlite_master WHERE type='table' AND name='{anime_id}';

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) )

Fail to run 'execute(sqlcmd)' of sqlite3 using Python,Ubuntu

I want to use sqlite3 to deal with data in Ubuntu with python. But I always failed and get errors. Codes related to database are as follows:
sqlite = "%s.db" % name
#connnect to the database
conn = sqlite3.connect(sqlite)
print "Opened database successfully"
c = conn.cursor()
#set default separator to "\t" in database
c.execute(".separator "\t"")
print "Set separator of database successfully"
#create table data_node
c.execute('''create table data_node(Time int,Node Text,CurSize int,SizeVar int,VarRate real,Evil int);''')
print "Table data_node created successfully"
node_info = "%s%s.txt" % (name,'-PIT-node')
c.execute(".import %\"s\" data_node") % node_info
print "Import to data_node successfully"
#create table data_face
data_info = "%s%s.txt" % (name,'-PIT-face')
c.execute('''create table data_face(Time int,Node Text,TotalEntry real,FaceId int,FaceEntry real,Evil int);''')
c.execute(".import \"%s\" data_face") % face_info
#get the final table : PIT_node
c.execute('''create table node_temp as select FIRST.Time,FIRST.Node,ROUND(FIRST.PacketsRaw/SECOND.PacketsRaw,4) as SatisRatio from tracer_temp FIRST,tracer_temp SECOND WHERE FIRST.Time=SECOND.Time AND FIRST.Node=SECOND.Node AND FIRST.Type='InData' AND SECOND.Type='OutInterests';''')
c.execute('''create table PIT_node as select A.Time,A.Node,B.SatisRatio,A.CurSize,A.SizeVar,A.VarRate,A.Evil from data_node A,node_temp B WHERE A.Time=B.Time AND A.Node=B.Node;''')
#get the final table : PIT_face
c.execute('''create table face_temp as select FIRST.Time,FIRST.Node,FIRST.FaceId,ROUND(FIRST.PacketsRaw/SECOND.PacketsRaw,4) as SatisRatio,SECOND.Packets from data_tracer FIRST,data_tracer SECOND WHERE FIRST.Time=SECOND.Time AND FIRST.Node=SECOND.Node AND FIRST.FaceId=SECOND.FaceId AND FIRST.Type='OutData' AND SECOND.Type='InInterests';''')
c.execute('''create table PIT_face as select A.Time,A.Node,A.FaceId,B.SatisRatio,B.Packets,ROUND(A.FaceEntry/A.TotalEntry,4),A.Evil from data_face as A,face_temp as B WHERE A.Time=B.Time AND A.Node=B.Node AND A.FaceId = B.FaceId;''')
conn.commit()
conn.close()
These sql-commands are right. When I run the code, it always shows sqlite3.OperationalError: near ".": syntax error. So how to change my code and are there other errors in other commands such as create table?

You have many problems in your code as posted, but the one you're asking about is:
c.execute(".separator "\t"")
This isn't valid Python syntax. But, even if you fix that, it's not valid SQL.
The "dot-commands" are special commands to the sqlite3 command line shell. It intercepts them and uses them to configure itself. They mean nothing to the actual database, and cannot be used from Python.
And most of them don't make any sense outside that shell anyway. For example, you're trying to set the column separator here. But the database doesn't return strings, it returns row objects—similar to lists. There is nowhere for a separator to be used. If you want to print the rows out with tab separators, you have to do that in your own print statements.
So, the simple fix is to remove all of those dot-commands.
However, there is a problem—at least one of those dot-commands actually does something:
c.execute(".import %\"s\" data_node") % node_info
You will have to replace that will valid calls to the library that do the same thing as the .import dot-command. Read what it does, and it should be easy to understand. (You basically want to open the file, parse the columns for each row, and do an executemany on an INSERT with the rows.)

select from insert into not working with sqlalchemy

I want to insert a record in mytable (in DB2 database) and get the id generated in that insert. I'm trying to do that with python 2.7. Here is what I did:
import sqlalchemy
from sqlalchemy import *
import ibm_db_sa
db2 = sqlalchemy.create_engine('ibm_db_sa://user:pswd#localhost:50001/mydatabase')
sql = "select REPORT_ID from FINAL TABLE(insert into MY_TABLE values(DEFAULT,CURRENT TIMESTAMP,EMPTY_BLOB(),10,'success'));"
result = db2.execute(sql)
for item in result:
id = item[0]
print id
When I execute the code above it gives me this output:
10 //or a increasing number
Now when I check in the database nothing has been inserted ! I tried to run the same SQL request on the command line and it worked just fine. Any clue why I can't insert it with python using sqlalchemy ?

Did you try a commit? #Lennart is right. It might solve your problem.
Your code does not commit the changes you have made and thus are rolled back.
If your Database is InnoDB, it is transactional and thus needs a commit.
according to this, you also have to connect to your engine. so in your instance it would look like:
db2 = sqlalchemy.create_engine('ibm_db_sa://user:pswd#localhost:50001/mydatabase')
conn = db2.connect()
trans = conn.begin()
try:
sql = "select REPORT_ID from FINAL TABLE(insert into MY_TABLE values(DEFAULT,CURRENT TIMESTAMP,EMPTY_BLOB(),10,'success'));"
result = conn.execute(sql)
for item in result:
id = item[0]
print id
trans.commit()
except:
trans.rollback()
raise
I do hope this helps.

Confirmation that a postgres 'update' query worked in python

I've written my first 'update' query in python, while it seems correct, I'm not sure how to receive back the output to confirm it worked..
This is supposed to load a CSV file and replace the values in the first column with those in the second:
def main():
try:
conn=psycopg2.connect("dbname='subs' user='subs' host='localhost' password=''")
except:
print "I am unable to connect to the database."
sys.exit()
with open("dne.txt", "r+") as f:
for line in f:
old = line.split(',')[0].strip()
new = line.split(',')[1].strip()
cur = conn.cursor()
cur.execute("UPDATE master_list SET subs = '{0}' WHERE subs = '{1}';".format(new, old))
conn.commit()
results = cur.fetchall()
for each in results:
print str(each)
if __name__=="__main__":
main()
I thought the results (UPDATE 1 for each change?) would come back as a tuple, but I got an error instead:
psycopg2.ProgrammingError: no results to fetch
I'm not sure if this means my query just didn't work and there were no updates, or if I can't use fetchall() like I'm trying to.
Any feedback or suggestions welcome!

The UPDATE statement won't return any values as you are asking the database to update its data not to retrieve any data.
By far the best way to get the number of rows updated is to use cur.rowcount. This works with other drivers too, like with Psycopg2 for Postgresql it's the same syntax.
cur.execute("UPDATE master SET sub = ('xyz') WHERE sub = 'abc'")
print(cur.rowcount)
A more roundabout way of checking the update is by running a SELECT against the table after updating it; you should get the data returned. In my example below the first SELECT will return the row(s) where the update will happen. The second SELECT after the update should then return no rows as you have already updated all fields. The third SELECT should return the rows you have updated, plus any that already existed with the 'xyz' value.
import sqlite3
def main():
try:
conn=sqlite3.connect(":memory:")
cur = conn.cursor()
cur.execute("create table master(id text, sub text)")
cur.execute("insert into master(id, sub) values ('1', 'abc')")
cur.execute("insert into master(id, sub) values ('2', 'def')")
cur.execute("insert into master(id, sub) values ('3', 'ghi')")
conn.commit()
except:
print("I am unable to connect to the database.")
sys.exit()
cur.execute("select id, sub from master where sub='abc'")
print(cur.fetchall())
cur.execute("UPDATE master SET sub = ('xyz') WHERE sub = 'abc'")
conn.commit()
cur.execute("select id, sub from master where sub='abc'")
print(cur.fetchall())
cur.execute("select id, sub from master where sub='xyz'")
print(cur.fetchall())
if __name__=="__main__":
main()

In PostgreSQL 9.5 or later you can add RETURNING * to end your query that then returns the modified rows.
PostgreSQL docs: https://www.postgresql.org/docs/9.5/dml-returning.html
Sometimes it is useful to obtain data from modified rows while they
are being manipulated. The INSERT, UPDATE, and DELETE commands all
have an optional RETURNING clause that supports this. Use of RETURNING
avoids performing an extra database query to collect the data, and is
especially valuable when it would otherwise be difficult to identify
the modified rows reliably.