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Python database connection not showing results

I'm using this simple script, however, the for loop never executes. The script is terminated without any error - but the data is in the database. 2 weeks ago this script worked fine.
Does anyone know where the problem may be?
Thank you.
import pyodbc
conn = pyodbc.connect(r'Driver={Microsoft Access Driver (*.mdb, *.accdb)};DBQ=S:\Chat_OV_UL\O2Spokojenost\DtbO2Spokojenost.accdb;', autocommit=True)
cursor = conn.cursor()
cursor.execute('select * from t_prepair')
print ("Databáze načtena")
limita = 0
for row in cursor.fetchall():
limita = limita + 1
print(row[0])
print(limita)
print("----")

update row in oracle from python timeout/take forever

I'm using cx_oracle to update record data in oracle from python. It just a simple update, but it takes forever to run and timeout in the end. If I run the same statement directly from Oracle, it works perfectly. Does anyone know why this happened? Thanks!
my code:
con = cx_Oracle.connect()
cur = con.cursor()
stmt = "UPDATE table SET rank = 4 WHERE id like 'SAP_1000141471' and rank = 2"
cur.execute(stmt)
con.commit()
result =cur.fetchall()

"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.

Python MySQL cursor fails to fetch rows

I am trying to fetch data from AWS MariaDB:
cursor = self._cnx.cursor()
stmt = ('SELECT * FROM flights')
cursor.execute(stmt)
print(cursor.rowcount)
# prints 2
for z in cursor:
print(z)
# Does not iterate
row = cursor.fetchone()
# row is None
rows = cursor.fetchall()
# throws 'No result set to fetch from.'
I can verify that table contains data using MySQL Workbench. Am I missing some step?
EDIT: re 2 answers:
res = cursor.execute(stmt)
# res is None
EDIT:
I created new Python project with a single file:
import mysql.connector
try:
cnx = mysql.connector.connect(
host='foobar.rds.amazonaws.com',
user='devuser',
password='devpasswd',
database='devdb'
)
cursor = cnx.cursor()
#cursor = cnx.cursor(buffered=True)
cursor.execute('SELECT * FROM flights')
print(cursor.rowcount)
rows = cursor.fetchall()
except Exception as exc:
print(exc)
If I run this code with simple cursor, fetchall raises "No result set to fetch from". If I run with buffered cursor, I can see that _rows property of cursor contains my data, but fetchall() returns empty array.

Your issue is that cursor.execute(stmt) returns an object with results and you're not storing that.
results = cursor.execute(stmt)
print(results.fetchone()) # Prints out and pops first row

For the future googlers with the same Problem I found a workaround which may help in some cases:
I didn't find the source of the problem but a solution which worked for me.
In my case .fetchone() also returned none whatever I did on my local(on my own Computer) Database. I tried the exact same code with the Database on our companies server and somehow it worked. So I copied the complete server Database onto my local Database (by using database dumps) just to get the server settings and afterwards I also could get data from my local SQL-Server with the code which didn't work before.
I am a SQL-newbie but maybe some crazy setting on my local SQL-Server prevented me from fetching data. Maybe some more experienced SQL-user knows this setting and can explain.

Sybase sybpydb queries not returning anything

I am currently connecting to a Sybase 15.7 server using sybpydb. It seems to connect fine:
import sys
sys.path.append('/dba/sybase/ase/15.7/OCS-15_0/python/python26_64r/lib')
sys.path.append('/dba/sybase/ase/15.7/OCS-15_0/lib')
import sybpydb
conn = sybpydb.connect(user='usr', password='pass', servername='serv')
is working fine. Changing any of my connection details results in a connection error.
I then select a database:
curr = conn.cursor()
curr.execute('use db_1')
however, now when I try to run queries, it always returns None
print curr.execute('select * from table_1')
I have tried running the use and select queries in the same execute, I have tried including go commands after each, I have tried using curr.connection.commit() after each, all with no success. I have confirmed, using dbartisan and isql, that the same queries I am using return entries.
Why am I not getting results from my queries in python?
EDIT:
Just some additional info. In order to get the sybpydb import to work, I had to change two environment variables. I added the lib paths (the same ones that I added to sys.path) to $LD_LIBRARY_PATH, i.e.:
setenv LD_LIBRARY_PATH "$LD_LIBRARY_PATH":dba/sybase/ase/15.7/OCS-15_0/python/python26_64r/lib:/dba/sybase/ase/15.7/OCS-15_0/lib
and I had to change the SYBASE path from 12.5 to 15.7. All this was done in csh.
If I print conn.error(), after every curr.execute(), I get:
("Server message: number(5701) severity(10) state(2) line(0)\n\tChanged database context to 'master'.\n\n", 5701)

I completely understand where you might be confused by the documentation. Its doesn't seem to be on par with other db extensions (e.g. psycopg2).
When connecting with most standard db extensions you can specify a database. Then, when you want to get the data back from a SELECT query, you either use fetch (an ok way to do it) or the iterator (the more pythonic way to do it).
import sybpydb as sybase
conn = sybase.connect(user='usr', password='pass', servername='serv')
cur = conn.cursor()
cur.execute("use db_1")
cur.execute("SELECT * FROM table_1")
print "Query Returned %d row(s)" % cur.rowcount
for row in cur:
print row
# Alternate less-pythonic way to read query results
# for row in cur.fetchall():
# print row
Give that a try and let us know if it works.

Python 3.x working solution:
import sybpydb
try:
conn = sybpydb.connect(dsn="Servername=serv;Username=usr;Password=pass")
cur = conn.cursor()
cur.execute('select * from db_1..table_1')
# table header
header = tuple(col[0] for col in cur.description)
print('\t'.join(header))
print('-' * 60)
res = cur.fetchall()
for row in res:
line = '\t'.join(str(col) for col in row)
print(line)
cur.close()
conn.close()
except sybpydb.Error:
for err in cur.connection.messages:
print(f'Error {err[0]}, Value {err[1]}')