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SQLITE with python : Adding the database name in SELECT statement

I am using sqlite3 with python, and after connecting to the database and creating a table, sqlite3 shows an error when I try to execute a SELECT statment on the table with the name of the databse in it :
con = sqlite3.connect("my_databse")
cur = con.cursor()
cur.execute('''CREATE TABLE my_table ... ''')
cur.execute("SELECT * FROM my_database.my_table") # this works fine without the name of the database before the table name
but I get this error from sqlite3 :
no such table : my_database.my_table
Is there a way to do a SELECT statment with the name of the database in it ?

The short answer is no you can't do this with SQLite. This is because you already specify the database name with sqlite3.connect() and SQLite3 doesn't allow multiple databases in the same file.

Make sure of the database is in the same directory with the python script. In order to verify this you can use os library and os.listdir() method. After connecting the database and creating the cursor, you can query with the table name.
cur.execute('SELECT * FROM my_table')

ORA-00942 when importing data from Oracle Database to Pandas

I try to import data from a oracle database to a pandas dataframe.
right Now i am using:
import cx_Oracle
import pandas as pd
db_connection_string = '.../A1#server:port/servername'
con = cx_Oracle.connect(db_connection_string)
query = """SELECT*
FROM Salesdata"""
df = pd.read_sql(query, con=con)
and get the following error: DatabaseError: ORA-00942: Table or view doesn't exist
When I run a query to get the list of all tables:
cur = con.cursor()
cur.execute("SELECT table_name FROM dba_tables")
for row in cur:
print (row)
The output looks like this:
('A$',)
('A$BD',)
('Salesdata',)
What I am doing wrong? I used this question to start.
If I use the comment to print(query)I get:
SELECT*
FROM Salesdata

Getting ORA-00942 when running SELECT can have 2 possible causes:
The table does not exist: here you should make sure the table name is prefixed by the table owner (schema name) as in select * from owner_name.table_name. This is generally needed if the current Oracle user connected is not the table owner.
You don't have SELECT privileges on the table. This is also generally needed if the current Oracle user connected is not the table owner.
You need to check both.

Python write to MySQL - no error but no writing

I am trying to write into my localhost MySQL database.
I have created a database named "test", a table called "price_update" and a row called "model"
When I run the script below I get no errors, however, I also get nothing written to my database.
I am not sure where to start looking for the problem. the row is varchar(10) and collation utf9_general_ci.
import MySQLdb
conn = MySQLdb.connect(host="127.0.0.1",user="someUser",passwd="somePassword",db="test")
query = "INSERT INTO price_update (model) values ('12345')"
x = conn.cursor()
x.execute(query)
row = x.fetchall()

You have to commit the changes:
conn.commit()
Also, I'd make your query safer:
query = "INSERT INTO price_update (model) values (%s)"
...
x.execute(query, ('12345',))

using python 2.7 to query sqlite3 database and getting "sqlite3 operational error no such table"

My simple test code is listed below. I created the table already and can query it using the SQLite Manager add-in on Firefox so I know the table and data exist. When I run the query in python (and using the python shell) I get the no such table error
def TroyTest(self, acctno):
conn = sqlite3.connect('TroyData.db')
curs = conn.cursor()
v1 = curs.execute('''
SELECT acctvalue
FROM balancedata
WHERE acctno = ? ''', acctno)
print v1
conn.close()

When you pass SQLite a non-existing path, it'll happily open a new database for you, instead of telling you that the file did not exist before. When you do that, it'll be empty and you'll instead get a "No such table" error.
You are using a relative path to the database, meaning it'll try to open the database in the current directory, and that is probably not where you think it is..
The remedy is to use an absolute path instead:
conn = sqlite3.connect('/full/path/to/TroyData.db')
You need to loop over the cursor to see results:
curs.execute('''
SELECT acctvalue
FROM balancedata
WHERE acctno = ? ''', acctno)
for row in curs:
print row[0]
or call fetchone():
print curs.fetchone() # prints whole row tuple

The problem is the SQL statment. you must specify the db name and after the table name...
'''SELECT * FROM db_name.table_name WHERE acctno = ? '''

Postgresql table update

I updated a database table using postgresql from python
My code was
import psycopg2
connection=psycopg2.connect("dbname=homedb user=ria")
cursor=connection.cursor()
l_dict= {'licence_id':1}
cursor.execute("SELECT * FROM im_entry.usr_table")
rows=cursor.fetchall()
for row in rows:
i=i+1
p = findmax(row)
#print p
idn="id"
idn=idn+str(i)
cursor.execute("UPDATE im_entry.pr_table SET (selected_entry) = ('"+p+"') WHERE image_1d ='"+idn+"'")
print 'DATABASE TO PRINT'
cursor.execute("SELECT * FROM im_entry.pr_table")
rows=cursor.fetchall()
for row in rows:
print row
I got the updated table displayed
But when i display updated table by psql as
homedb=# SELECT * FROM im_entry.pr_table;
i got an empty table displayed..what is wrong?? please help me

You're probably not committing the transaction, i.e. you need a connection.commit() after all your updates.
There are various different settings you can make to the isolation level, e.g. autocommit, so you don't need to issue commits yourself. See, for example, How do I do database transactions with psycopg2/python db api?