What exceptions can be returned from Pandas read_sql ()

Question

I have a custom function that uses pymysql to connect to a mysql database and then query the database and read the results in the Pandas framework.

import pandas as pd
import pymysql
import getpass

def myGetData(myQuery):

    myServer = 'xxx.xxx.xxx.xxx'
    myUser = input("Enter MySQL database username: ")
    myPwd = getpass.getpass("Enter password: ")

    myConnection = pymysql.connect(host=myServer,user=myUser,password=myPwd)

    myTempDF = pd.io.sql.read_sql(myQuery, con=myConnection)

    myConnection.close()

    return myTempDF

myDF = myGetData("SELECT * FROM `myDB`.`myTable`")

, pymysql.connect(), . , read_sql(). , ? Pandas (http://pandas.pydata.org/pandas-docs/version/0.19.2/generated/pandas.read_sql.html), . , , , Python. , read_sql()?

, , , , . , , , / , . - :

OperationalError: (1045, "Access denied for user 'yyy'@'xxx.xxx.xxx.xxx' (using password: YES)")

, :

try:
    phjConnection = pymysql.connect(host=phjServer, user=phjUser, password=phjPwd)

except pymysql.OperationalError as e:
            print("\nAn OperationalError occurred. Error number {0}: {1}.".format(e.args[0],e.args[1]))

( , OperationalError pymysql.OperationalError ).

Pandas real_sql() SQL-. , , OperationalError, DatabaseError:

OperationalError: (1142, "SELECT command denied to user 'yyy'@'xxx.xxx.xxx.xxx' for table 'table'")

During handling of the above exception, another exception occurred:

DatabaseError: Execution failed on sql 'SELECT * FROM `db`.`table`': (1142, "SELECT command denied to user 'yyy'@'xxx.xxx.xxx.xxx' for table 'table'")

, OperationalError. pymysql.OperationalError . , , . , ? , - , . .

2

:

import pandas as pd
import pymysql
import getpass

def myGetData(myQuery):

    myServer = 'xxx.xxx.xxx.xxx'
    myUser = input("Enter MySQL database username: ")
    myPwd = getpass.getpass("Enter password: ")

    try:
        myConnection = pymysql.connect(host=myServer,user=myUser,password=myPwd)

    except pymysql.OperationalError as e:
        # Catching this exception works fine if, for example,
        # I enter the wrong username and password
        print("\nAn OperationalError occurred. Error number {0}: {1}.".format(e.args[0],e.args[1]))

    try:
        myTempDF = pd.io.sql.read_sql(myQuery, con=myConnection)

    except pymysql.OperationalError as e:
        # However, this error isn't picked up following an incorrect
        # SQL query despite the error message saying that an
        # OperationalError has occurred.
        # Many variations on this theme have been tried but failed.
        print("\nAn error occurred. Error number {0}: {1}.".format(e.args[0],e.args[1]))

    myConnection.close()

    return myTempDF

myDF = myGetData("SELECT * FROM `myDB`.`myTable`")

Answer 1

, , read_sql - 'read_sql_table read_sql_query. source, a ValueError . , ValueError . ( )

Answer 2

, SQLalchemy..

try:
        df = pd.read_sql_query(QUERY, engine)
    except sqlalchemy.exc.OperationalError as e:
        logger.Info('Error occured while executing a query {}'.format(e.args))

. SQL