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pyodbc cursor.execute (query) adds my username in front of the table from database

In Jupyter Notebook, I was able to connect to my work database using pyobdc with 'dsn; userid; pw' connection string successfully. I tested out printing all the table names in the database. Then I tried to run the following code to test a simple query.
================================
query = "select * from TEST_TABLE"
cursor.execute(query)
================================
But I got the following error.
ProgrammingError: ('42S02', '[42S02] [IBM][CLI Driver][DB2/AIX64] SQL0204N "**myusername.TEST_TABLE**" is an **undefined name**. SQLSTATE=42704\r\n (-204) (SQLExecDirectW)')
TEST_TABLE does exist in the database I'm connected to. But for some reason, the code is adding myusername in front of the TEST_TABLE and tells me the table name is not defined.

Try setting up the PyODBC connection as follows:
import pyodbc
dbConn = pyodbc.connect("DSN=<dsn>;UID=<uid>;PWD=<pwd>;DATABASE=<db>")
dbCursor = dbConn.cursor()
query = "SELECT * FROM TEST_TABLE"
dbCursor.execute(query)
where:
dsn = the hostname (or IP address)
uid = the username
pwd = the password
db = the database name

PostgreSQL Error while executing sql command in Python

i've been trying to get some data from my db by using below code, but the code is not working. is there any mistake that i made in the code, if so how can i fix it.
NOTE: i took the below code from just a script not a django or flesk web app.
def db():
conn = psycopg2.connect(
"dbname=mydb user=postgres password=****** host=*.*.*.*")
cur = conn.cursor()
cur.execute("""SELECT * FROM MddPublisher""")
query_results = cur.fetchall()
print(query_results)
db()
ERROR: psycopg2.errors.UndefinedTable: relation "mddpublisher" does not exist LINE 1: SELECT * FROM MddPublisher
additionally,i want to show below code to prove that connection is ok. the problem is that i can't receive data from my db whenever i try to execute select command through python.
def print_tables():
conn = psycopg2.connect(
"dbname=mydb user=postgres password=***** host=*.*.*.*.*")
cur = conn.cursor()
cur.execute("""SELECT table_name FROM information_schema.tables
WHERE table_schema = 'public'""")
for table in cur.fetchall():
print(table)
print_tables()
OUTPUT:
('MddPublisher',)

This is probably an issue with case sensitivity. Postgresql names are usually normalized to lower case. However, when used inside double quotes, they keep their case. So, to access a table named MddPublisher you must write it like "MddPublisher".
All the gory details are in Section 4.1.1, Identifiers and Key Words in the Postgresql 14 docs.

Python cx_Oracle module: unable to format query in code

I am using cx_Oracle module to connect to oracle database. In the script i use two variables schema_name and table_name. The below query works fine
cur1.execute("select owner,table_name from dba_tables where owner ='schema_name'")
But i need to query the num of rows of a table, where i need to qualify the table_name with the schema_name and so the query should be
SELECT count(*) FROM "schema_name"."table_name"
This does not work when using in the code, i have tried to put it in triple quotes, single quotes and other options but it does not format the query as expected and hence errors out with table does not exist.
Any guidance is appreciated.

A prepared statement containing placeholders with variables of the form ...{}.{}".format(sc,tb) might be used
sc='myschema'
tb='mytable'
cur1.execute("SELECT COUNT(*) FROM {}.{}".format(sc,tb))
print(cur1.fetchone()[0])

In this particular case, you could also try setting Connection.current_schema, see the cx_Oracle API doc
For example, if you create table in your own schema:
SQL> show user
USER is "CJ"
SQL> create table ffff (mycol number);
Table created.
SQL> insert into ffff values (1);
1 row created.
SQL> commit;
Commit complete.
Then run Python code that connects as a different user:
import cx_Oracle
import os
import sys, os
if sys.platform.startswith("darwin"):
cx_Oracle.init_oracle_client(lib_dir=os.environ.get("HOME")+"/Downloads/instantclient_19_8")
username = "system"
password = "oracle"
connect_string = "localhost/orclpdb1"
connection = cx_Oracle.connect(username, password, connect_string)
connection.current_schema = 'CJ';
with connection.cursor() as cursor:
sql = """select * from ffff"""
for r in cursor.execute(sql):
print(r)
sql = """select sys_context('USERENV','CURRENT_USER') from dual"""
for r in cursor.execute(sql):
print(r)
the output will be:
(1,)
('SYSTEM',)
The last query shows that it is not the user that is being changed, but just the first query is automatically changed from 'ffff' to 'CJ.ffff'.

"Invalid cursor state" error when executing a batch that includes a USE statement

I tried retrieving data from a Microsoft SQL database using pypyodbc 1.3.3 with Python 3.5 on Windows but got a pypyodbc.ProgrammingError '[24000] [Microsoft] [SQL Server Native Client 11.0] Invalid cursor state' using the following code:
import pypyodbc
conn = pypyodbc.connect(r'DRIVER={SQL Server Native Client 11.0};SERVER=server;DATABASE=database;UID=uid;PWD=pwd')
cursor = conn.cursor()
sql = '''USE database;
SELECT R0
FROM table;'''
cursor.execute(sql)
results = cursor.fetchone()
print(results)
The SQL works in Microsoft SQL Server Management Studio, the connection and executing worked in another script i wrote to insert into the same database and also works if i remove
results = cursor.fetchone()
So far I tried cursor.fetchone(), cursor.fetchall() and list(cursor) but all produced the same result which leads me to believe that the command itself isn't the problem.
According to this microsoft site it means that there isn't an open cursor, but I can get it's description, so from my understanding there has to be.

It's not a matter of being unable to execute a USE ... statement at all, it's just that we cannot do that as part of a multi-statement batch. So, this will not work ...
crsr.execute("""\
USE master;
SELECT TOP 2 name FROM sys.tables ORDER BY name;
""")
rows = crsr.fetchall() # error
... but this will work fine
crsr.execute("USE master")
crsr.execute("SELECT TOP 2 name FROM sys.tables ORDER BY name")
rows = crsr.fetchall()
(Tested with both pypyodbc 1.3.4 and pyodbc 4.0.21)

I had a similar issue. I was able to resolve this by removing the "USE Database" statement.
You already connected to your db here:
conn = pypyodbc.connect(r'DRIVER={SQL Server Native Client 11.0};SERVER=server;DATABASE=database;UID=uid;PWD=pwd')

Dynamic table names within MYSQL statement (Google Cloud SQL)

I am trying to drop/delete a table from within Google Cloud SQL using Python (App Engine) but I want the table name to be based on a variable, for simplicity I am using 'hello' here. For some reason it is throwing back an error at me: "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-IN' at line 1"
I tried the following:
tabNameShort = 'hello'
cursor = conn.cursor()
cursor.execute('DROP TABLE IF EXISTS %s', (tabNameShort))
conn.commit()
I also tried:
tabNameShort = 'hello'
cursor = conn.cursor()
cursor.execute('DROP TABLE IF EXISTS ' + tabNameShort)
conn.commit()
Any suggestions?

try this:
tabNameShort = 'hello'
cursor = conn.cursor()
cursor.execute('DROP TABLE IF EXISTS `%s`' % tabNameShort)
conn.commit()

A warning: appending the table name directly using '+' can result in an SQL injection vulnerability, if the table name is derived, directly or indirectly, from user input.