预期的字符串或字节对象

Question

I am taking an excel spreadsheet, loading into a Pandas Dataframe then appending the data frame to an Oracle table.

Any potentially sensitive data is starred.

import os
import pandas as pd
import cx_Oracle
from tkinter import Tk
from tkinter.filedialog import askopenfilename
from sqlalchemy import create_engine

#Gets excel file and writes to dataframe
Tk().withdraw()
filename = askopenfilename()
xl = pd.ExcelFile(filename)
print(xl.sheet_names)
ws = input('Type a sheet name to load: \n')
dFrame = xl.parse(ws)

#create engine connection
engine = create_engine('oracle+cx_oracle://*********')
print("Engine created")

with engine.begin() as conn:
    conn.execute("DELETE FROM table")
print("Delete from executed")

#Write dataframe to table
dFrame.to_sql('table',con=engine, if_exists='append', index=False)
print("Data frame appended to table")

However, I get error TypeError: expecting string or bytes object (full trace below), I believe this means there is a column in the dataframe which does not match the existing table type.

If that is the case, how can I find which section of the dataframe is causing a problem?

Traceback (most recent call last):
  File "C:\Users\*****\Documents\CD\Test.py", line 26, in <module>
    dFrame.to_sql('table',con=engine, if_exists='append', index=False)
  File "C:\Users\*****\AppData\Local\Programs\Python\Python37-32\lib\site-packages\pandas\core\generic.py", line 2130, in to_sql
    dtype=dtype)
  File "C:\Users\*****\AppData\Local\Programs\Python\Python37-32\lib\site-packages\pandas\io\sql.py", line 450, in to_sql
    chunksize=chunksize, dtype=dtype)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\pandas\io\sql.py", line 1127, in to_sql
    table.insert(chunksize)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\pandas\io\sql.py", line 641, in insert
    self._execute_insert(conn, keys, chunk_iter)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\pandas\io\sql.py", line 616, in _execute_insert
    conn.execute(self.insert_statement(), data)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\sqlalchemy\engine\base.py", line 948, in execute
    return meth(self, multiparams, params)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\sqlalchemy\sql\elements.py", line 269, in _execute_on_connection
    return connection._execute_clauseelement(self, multiparams, params)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\sqlalchemy\engine\base.py", line 1060, in _execute_clauseelement
    compiled_sql, distilled_params
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\sqlalchemy\engine\base.py", line 1200, in _execute_context
    context)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\sqlalchemy\engine\base.py", line 1416, in _handle_dbapi_exception
    util.reraise(*exc_info)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\sqlalchemy\util\compat.py", line 249, in reraise
    raise value
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\sqlalchemy\engine\base.py", line 1170, in _execute_context
    context)
  File "C:\Users\******\AppData\Local\Programs\Python\Python37-32\lib\site-packages\sqlalchemy\dialects\oracle\cx_oracle.py", line 969, in do_executemany
    cursor.executemany(statement, parameters)
TypeError: expecting string or bytes object

EDIT:

This is the datatypes for each column in pandas and oracle, respectively:

Column1 | int64          | NUMBER(10,0)
Column2 | object         | VARCHAR2(128 BYTE)
Column3 | int64          | NUMBER(13,0)
Column4 | object         | VARCHAR2(128 BYTE)
Column5 | object         | VARCHAR2(128 BYTE)
Column6 | float64        | NUMBER(10,0)
Column7 | object         | VARCHAR2(128 BYTE)
Column8 | object         | VARCHAR2(128 BYTE)
Column9 | int64          | NUMBER(5,0)
Column10| datetime64[ns] | DATE
Column11| datetime64[ns] | DATE
Column12| int64          | NUMBER(10,0)
Column13| float64        | NUMBER(10,0)
Column14| object         | VARCHAR2(128 BYTE)
Column15| float64        | NUMBER(10,0)

None of those should be causing issues, right?

Answer 1

would you please check if any 'Nan' in your Dataframe? Actually I got the same error yesterday, and after add below code in my script, the dataframe has been appended to a oracle table successfully.

df = df.fillna('na')