I am trying to run a python script from VB.Net using IronPython. So far, I have installed Python and IronPython. I have the ExecPython method shown below. It works fine when I call a simple print/hello world type of script. This DBTest.py script is just using pyodbc and connecting to the database and executing a basic select query.
The error I get at the source.Execute(scope) line is "IronPython.Runtime.Exceptions.ImportException: 'No module named 'pyodbc''"
I've installed pyodbc using pip install pyodbc. The DBTest.py script runs fine when I run it with IDLE.
I'm not sure if this is a limitation or if there's something I'm missing in the setup.
Thanks in advance for your help!!
Sub ExecPython(ByVal argv As List(Of String))
Dim engine As ScriptEngine = Python.CreateEngine
Dim scriptPath As String = "C:\scripts\DBTest.py"
Dim source As ScriptSource = engine.CreateScriptSourceFromFile(scriptPath)
argv.Add("")
engine.GetSysModule.SetVariable("argv", argv)
engine.SetSearchPaths({"C:\Users\MYUSERNAME\AppData\Local\Programs\Python\Python39\Scripts",
"C:\Users\MYUSERNAME\AppData\Local\Programs\Python\Python39\include",
"C:\Users\MYUSERNAME\AppData\Local\Programs\Python\Python39\Lib",
"C:\Program Files\IronPython 3.4\Lib"})
Dim eIO As ScriptIO = engine.Runtime.IO
Dim errors As New MemoryStream
eIO.SetErrorOutput(errors, Text.Encoding.Default)
Dim results As New MemoryStream
eIO.SetOutput(results, Text.Encoding.Default)
Dim scope As ScriptScope = engine.CreateScope
source.Execute(scope)
Console.WriteLine("ERRORS:")
Console.WriteLine(FormatResult(errors.ToArray))
Console.WriteLine("")
Console.WriteLine("RESULTS:")
Console.WriteLine(FormatResult(results.ToArray))
End Sub
Here is the python script that I am calling. It runs when I run the module from IDLE.
import pyodbc
conn = pyodbc.connect('Driver={SQL Server};'
'Server=MYSERVERNAME;'
'Database=MYDBNAME;'
'Trusted_Connection=yes;')
cursor = conn.cursor() cursor.execute('SELECT * FROM dbo.TABLENAME')
for row in cursor:
print(row)
It's been a while, probably you already found a solution.
But in general, for being able to use the 'module' you need to import clr and use the addReference function. Then you must do an import of the namespace with the python style.
Example:
import clr
clr.AddReference('System')
from System import *
Related
I have run into a peculiar issue while using the teradatasql package (installed from pypi). I use the following code (let's call it pytera.py) to query a database:
from dotenv import load_dotenv
import pandas as pd
import teradatasql
# Load the database credentials from .env file
_ = load_dotenv()
db_host = os.getenv('db_host')
db_username = os.getenv('db_username')
db_password = os.getenv('db_password')
def run_query(query):
"""Run query string on teradata and return DataFrame."""
if query.strip()[-1] != ';':
query += ';'
with teradatasql.connect(host=db_host, user=db_username,
password=db_password) as connect:
df = pd.read_sql(query, connect)
return df
When I import this function in the IPython/Python interpreter or in Jupyter Notebook, I can run queries just fine like so:
import pytera as pt
pt.run_query('select top 5 * from table_name;')
However, if I save the above code in a .py file and try to run it, I get an error message most of the time (not all the time). The error message is below.
E teradatasql.OperationalError: [Version 16.20.0.49] [Session 0] [Teradata SQL Driver] Hostname lookup failed for None
E at gosqldriver/teradatasql.(*teradataConnection).makeDriverError TeradataConnection.go:1046
E at gosqldriver/teradatasql.(*Lookup).getAddresses CopDiscovery.go:65
E at gosqldriver/teradatasql.discoverCops CopDiscovery.go:137
E at gosqldriver/teradatasql.newTeradataConnection TeradataConnection.go:133
E at gosqldriver/teradatasql.(*teradataDriver).Open TeradataDriver.go:32
E at database/sql.dsnConnector.Connect sql.go:600
E at database/sql.(*DB).conn sql.go:1103
E at database/sql.(*DB).Conn sql.go:1619
E at main.goCreateConnection goside.go:229
E at main._cgoexpwrap_e6e101e164fa_goCreateConnection _cgo_gotypes.go:214
E at runtime.call64 asm_amd64.s:574
E at runtime.cgocallbackg1 cgocall.go:316
E at runtime.cgocallbackg cgocall.go:194
E at runtime.cgocallback_gofunc asm_amd64.s:826
E at runtime.goexit asm_amd64.s:2361
E Caused by lookup None on <ip address redacted>: server misbehaving
I am using Python 3.7.3 and teradatasql 16.20.0.49 on Ubuntu (WSL) 18.04.
Perhaps not coincidentally, I run into a similar issue when trying a similar workflow on Windows (using the teradata package and the Teradata Python drivers installed). Works when I connect inside the interpreter or in Jupyter, but not in a script. In the Windows case, the error is:
E teradata.api.DatabaseError: (10380, '[08001] [Teradata][ODBC] (10380) Unable to establish connection with data source. Missing settings: {[DBCName]}')
I have a feeling that there's something basic that I'm missing, but I can't find a solution to this anywhere.
Thanks ravioli for the fresh eyes. Turns out the issue was loading in the environment variables using dotenv. My module is in a Python package (separate folder), and my script and .env files are in the working directory.
dotenv successfully reads in the environment variables (.env in my working directory) when I run the code in my original post, line by line, in the interpreter or in Jupyter. However, when I run the same code in a script, it does not find in the .env file in my working directory. That will be a separate question I'll have to find the answer to.
import teradatasql
import pandas as pd
def run_query(query, db_host, db_username, db_password):
"""Run query string on teradata and return DataFrame."""
if query.strip()[-1] != ';':
query += ';'
with teradatasql.connect(host=db_host, user=db_username,
password=db_password) as connect:
df = pd.read_sql(query, connect)
return df
The code below runs fine in a script now:
import pytera as pt
from dotenv import load_dotenv()
_ = load_dotenv()
db_host = os.getenv('db_host')
db_username = os.getenv('db_username')
db_password = os.getenv('db_password')
data = pt.run_query('select top 5 * from table_name;', db_host, db_username, db_password)
It looks like your client can't find the Teradata server, which is why you see that DBCName missing error. This should be the "system name" of your Teradata server (i.e. TDServProdA).
A couple things to try:
If you are trying to connect directly with a hostname, try disabling COP discovery in your connection with this flag: cop = false. More info
Try updating your hosts file on your local system. From the documentation:
Modifying the hosts File
If your site does not use DNS, you must define the IP address and the
Teradata Database name to use in the system hosts file on the
computer.
Locate the hosts file on the computer. This file is typically located in the following folder: %SystemRoot%\system32\drivers\etc
Open the file with a text editor, such as Notepad.
Add the following entry to the file: xxx.xx.xxx.xxx sssCOP1 where xxx.xx.xxx.xxx is the IP address and where sss is the Teradata
Database name.
Save the hosts file.
Link 1
Link 2
Being a newbie to python, trying to write a python code to connect to the oracle database without using any Instant client. i'm using jaydebeapi and jpype as suggested in some other threads in this forum. After lot of hurdles, i now got stuck at this error. here is the code.
import jaydebeapi
import jpype
try:
con = jaydebeapi.connect('oracle.jdbc.driver.OracleDriver', ['windb19.ams.com', 'AA3112D1OS', 'advantage', 'C:\Tools\ojdbc8.jar'])
cur = con.cursor()
cur.execute('select * from r_sc_user_info')
except Exception as e:
print e
and the error i'm receiving is as below
C:\Python27\python.exe C:/Project/Robot_Framework/SampleProject/CustomLibraries/DBLibrary.py
java.lang.Exception: Class oracle.jdbc.driver.OracleDriver not found
Process finished with exit code 0
As I couldn't modify anything in the Environment variables, as per the policy, I had to modify the code as below to make it work. I had to keep the ojdbc8.jar in the same path as that of this python file and add following lines of code.
jar=os.getcwd()+'\ojdbc8.jar'
args = '-Djava.class.path=%s' % jar
jvm_path = jpype.getDefaultJVMPath()
jpype.startJVM(jvm_path, args)
try:
con = jaydebeapi.connect("oracle.jdbc.driver.OracleDriver", "jdbc:oracle:thin:#HOSTNAME",["USERID", "PASSWORD"], jar)
I am very new to python and I just can't seem to find an answer to this error. When I run the code below I get the error
AttributeError: module 'odbc' has no attribute 'connect'
However, the error only shows in eclipse. There's no problem if I run it via command line. I am running python 3.5. What am I doing wrong?
try:
import pyodbc
except ImportError:
import odbc as pyodbc
# Specifying the ODBC driver, server name, database, etc. directly
cnxn = pyodbc.connect('DRIVER={SQL Server};SERVER=PXLstr,17;DATABASE=Dept_MR;UID=guest;PWD=password')
The suggestion to remove the try...except block did not work for me. Now the actual import is throwing the error as below:
Traceback (most recent call last):
File "C:\Users\a\workspace\TestPyProject\src\helloworld.py", line 2, in <module>
import pyodbc
File "C:\Users\a\AppData\Local\Continuum\Anaconda3\Lib\site-packages\sqlalchemy\dialects\mssql\pyodbc.py", line 105, in <module>
from .base import MSExecutionContext, MSDialect, VARBINARY
I do have pyodbc installed and the import and connect works fine with the command line on windows.
thank you
The problem here is that the pyodbc module is not importing in your try / except block. I would highly recommend not putting import statements in try blocks. First, you would want to make sure you have pyodbc installed (pip install pyodbc), preferably in a virtualenv, then you can do something like this:
import pyodbc
cnxn = pyodbc.connect('DRIVER={SQL Server};SERVER=PXLstr,17;DATABASE=Dept_MR;UID=guest;PWD=password')
cursor = cnxn.cursor()
cursor.execute('SELECT 1')
for row in cursor.fetchall():
print(row)
If you're running on Windows (it appears so, given the DRIVER= parameter), take a look at virtualenvwrapper-win for managing Windows Python virtual environments: https://pypi.python.org/pypi/virtualenvwrapper-win
Good luck!
Flipper's answer helped to establish that the problem was with referencing an incorrect library in External Libraries list in eclipse. After fixing it, the issue was resolved.
What is the name of your python file? If you inadvertently name it as 'pyodbc.py', you got that error. Because it tries to import itself instead of the intended pyodbc module.
here is the solution!
simply install and use 'pypyodbc' instead of 'pyodbc'!
I have my tested example as below. change your data for SERVER_NAME and DATA_NAME and DRIVER. also put your own records.good luck!
import sys
import pypyodbc as odbc
records = [
['x', 'Movie', '2020-01-09', 2020],
['y', 'TV Show', None, 2019]
]
DRIVER = 'ODBC Driver 11 for SQL Server'
SERVER_NAME = '(LocalDB)\MSSQLLocalDB'
DATABASE_NAME = 'D:\ASPNET\SHOJA.IR\SHOJA.IR\APP_DATA\DATABASE3.MDF'
conn_string = f"""
Driver={{{DRIVER}}};
Server={SERVER_NAME};
Database={DATABASE_NAME};
Trust_Connection=yes;
"""
try:
conn = odbc.connect(conn_string)
except Exception as e:
print(e)
print('task is terminated')
sys.exit()
else:
cursor = conn.cursor()
insert_statement = """
INSERT INTO NetflixMovies
VALUES (?, ?, ?, ?)
"""
try:
for record in records:
print(record)
cursor.execute(insert_statement, record)
except Exception as e:
cursor.rollback()
print(e.value)
print('transaction rolled back')
else:
print('records inserted successfully')
cursor.commit()
cursor.close()
finally:
if conn.connected == 1:
print('connection closed')
conn.close()
I want to use a variable in my SQL script. Variable's value is 100 (just a number). I have stored it as a csv. file in this directory: C:\Users\Dino\Desktop\my_file.csv.
I want in the sql script to run this:
import os
from ask_db import ask_db_params #this script creates the connection to the database
import sys, os
def my_function(cur, conn):
sql="""
\set outputdir'C:\\Users\\Dino\\Desktop'
\set new_var :outputdir '\\my_file.csv'
copy my_file to :'new_var';"""
cur.execute(sql)
conn.commit()
if __name__ == '__main__':
try:
conn = ask_db_params()
cur = conn.cursor()
analysis_data(cur,conn)
logging.info('Data analysed.')
except Exception as e:
logging.error('Failure', exc_info=True)
exit(1)
I have the error:
syntax error at or near "\" ....
It refers to the first line.
Any help regarding the syntax?
P.S. I m running python to call the sql script. Windows OS
That won't work. \set is a psql command, not an SQL command.
You will have to use string manipulation in Python to construct an SQL string that looks like this:
COPY my_file TO 'C:\Users\Dino\Desktop\my_file.csv'
Then use execute() with that SQL string.
This might be an obvious error but I'm trying to create a database within python from a script I've already created.
conn = sqlite3.connect('testDB')
c = conn.cursor()
c.execute('.read create.sql')
This gives an error "sqlite3.OperationalError: near ".": syntax error"
If I do the same thing at the sqlite3 cmd line it works fine
[me#myPC ~]$ sqlite3 testDB
SQLite version 3.3.6
Enter ".help" for instructions
sqlite> .read create.sql
sqlite>
It seems that any commands that start with a . give me problems.
just pass the content of the file to the .execute method:
conn = sqlite3.connect('testDB')
c = conn.cursor()
SQL = open('create.sql').read()
c.executescript(SQL)
I would suppose that commands starting with . are for the CLI client itself, not for the backend.
So you have no chance to do so and would have to do file reading and executing the queries by yourself, i.e. in Python.