"No driver name specified" writing pandas data frame into SQL Server table
I am trying to write a Pandas' DataFrame into an SQL Server table. Here is my example:
import pyodbc
import pandas as pd
import sqlalchemy
df = pd.DataFrame({'MDN': [242342342] })
engine = sqlalchemy.create_engine('mssql://localhost/Sandbox?trusted_connection=yes')
df.to_sql('Test',engine, if_exists = 'append',index = False)
I am getting the following error message. Any thoughts on how to fix?
c:\python34\lib\site-packages\sqlalchemy\connectors\pyodbc.py:82: SAWarning: No driver name specified; this is expected by PyODBC when using DSN-less connections
"No driver name specified; "
---------------------------------------------------------------------------
AttributeError Traceback (most recent call last)
<ipython-input-25-78677a18ce2d> in <module>()
4 engine = sqlalchemy.create_engine('mssql://localhost/Sandbox?trusted_connection=yes')
5
----> 6 df.to_sql('Test',engine, if_exists = 'append',index = False)
7
8 #cnxn.close()
c:\python34\lib\site-packages\pandas\core\generic.py in to_sql(self, name, con, flavor, schema, if_exists, index, index_label, chunksize, dtype)
980 self, name, con, flavor=flavor, schema=schema, if_exists=if_exists,
981 index=index, index_label=index_label, chunksize=chunksize,
--> 982 dtype=dtype)
983
984 def to_pickle(self, path):
c:\python34\lib\site-packages\pandas\io\sql.py in to_sql(frame, name, con, flavor, schema, if_exists, index, index_label, chunksize, dtype)
547 pandas_sql.to_sql(frame, name, if_exists=if_exists, index=index,
548 index_label=index_label, schema=schema,
--> 549 chunksize=chunksize, dtype=dtype)
550
551
c:\python34\lib\site-packages\pandas\io\sql.py in to_sql(self, frame, name, if_exists, index, index_label, schema, chunksize, dtype)
1564 if_exists=if_exists, index_label=index_label,
1565 dtype=dtype)
-> 1566 table.create()
1567 table.insert(chunksize)
1568
c:\python34\lib\site-packages\pandas\io\sql.py in create(self)
646
647 def create(self):
--> 648 if self.exists():
649 if self.if_exists == 'fail':
650 raise ValueError("Table '%s' already exists." % self.name)
c:\python34\lib\site-packages\pandas\io\sql.py in exists(self)
634
635 def exists(self):
--> 636 return self.pd_sql.has_table(self.name, self.schema)
637
638 def sql_schema(self):
c:\python34\lib\site-packages\pandas\io\sql.py in has_table(self, name, schema)
1577 query = flavor_map.get(self.flavor)
1578
-> 1579 return len(self.execute(query, [name,]).fetchall()) > 0
1580
1581 def get_table(self, table_name, schema=None):
c:\python34\lib\site-packages\pandas\io\sql.py in execute(self, *args, **kwargs)
1465 cur = self.con
1466 else:
-> 1467 cur = self.con.cursor()
1468 try:
1469 if kwargs:
AttributeError: 'Engine' object has no attribute 'cursor'
Also, is there ways to write connection string for create_engine differently? I would love to write it in form of a dictionary rather than a string.
Update: Here is my new environment:
MS SQL Server: Microsoft SQL Server 2012 - 11.0.2100.60 (X64) Feb 10 2012 19:39:15 Copyright (c) Microsoft Corporation Standard Edition (64-bit) on Windows NT 6.2 (Build 9200: )
Python: 3.4.3 (v3.4.3:9b73f1c3e601, Feb 24 2015, 22:43:06) [MSC v.1600 32 bit (Intel)]
Pandas version: '0.16.2'
sqlalchemy version: 1.1.3
Jupyter server version : 4.2.3
Now the line
engine = sqlalchemy.create_engine('mssql+pyodbc://localhost/Sandbox?trusted_connection=yes')
generates the following error:
c:\python34\lib\site-packages\sqlalchemy\connectors\pyodbc.py:82: SAWarning: No driver name specified; this is expected by PyODBC when using DSN-less connections
"No driver name specified; "
Answer
You need to specify both that you want to use ODBC and what ODBC driver to use.
engine = sqlalchemy.create_engine('mssql+pyodbc://localhost/Sandbox?driver=SQL+Server+Native+Client+11.0')
Trusted connections are the default, so you don't need to specify that, although it shouldn't hurt to do so.