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KeyError: 'TABLENAME' in mySQL database while using SQLAlchemy

I'm fairly new to the SQLAlchemy ORM. Im using a mySQL database whose schema I imported in a .sql file. I created the engine, connected to the database. I bound both the MetaData and the Session objects to the engine. But when I ran:
for t in metadata.tables:
print(t.name)
I got the following error:
fkey["referred_table"] = rec["TABLENAME"]
KeyError: 'TABLENAME'
So what am I doing wrong here? It is something elementary?
Below is the full code:
import sqlalchemy
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from sqlalchemy import *
engine = create_engine('mysql://sunnyahlawat:miq182#localhost/sqsunny')
engine.connect()
Session = sessionmaker(bind=engine)
session = Session()
metadata = MetaData(bind = engine, reflect = True)
#metadata.reflect(bind = engine)
for t in metadata.tables:
print(t.name)
#print(engine.table_names())

If the database being referred is a data dump and the table in question has foreign keys linked to an external database which has not been exported and is not on the same server, this error can come up.
The foreign key constraint fails in such a case.
A possible solution is to drop the constraint - if this is being tried out just in a test environment.

Python - Convert pyodbc code to SQLAlchemy

I have pyodbc code that I use to connect to a DSN, however for some reason it is no longer working and I cannot figure out why (the drivers are empty even though they are there).
So I want to try and convert everything to use SQLAlchemy instead.
My current code for connecting to the database is:
conn = pyodbc.connect('DSN=QueryBuilder')
cursor = conn.cursor()
stringA = "SELECT GrantInformation.Call FROM GrantInformation"
cursor.execute(stringA)
rows = cursor.fetchall()
How would I get this to do the same in SQLAlchemy, I have checked the documentation and I am still confused.
Many thanks
I used:
from sqlalchemy import create_engine
engine = create_engine("""{}://{}:{}#{}/{}"""
.format(SQL Server,nick,mypassword,myservername,querybuilder))
df = pd.read_sql_query("SELECT GrantInformation.Call FROM GrantInformation")
and I got:
File "<ipython-input-5-f7837462519f>", line 4
.format(SQL Server,nick,mypassword,myservername,querybuilder))
^
SyntaxError: invalid syntax
Also declared the variables before, and I now get:
ArgumentError: Could not parse rfc1738 URL from string 'SQL Server://nick:mypassword#myhost/querybuilder'

from sqlalchemy import create_engine
engine = create_engine("""{}://{}:{}#{}/{}"""
.format(driver,user,password,host,database))
df = pd.read_sql_query("SELECT GrantInformation.Call FROM GrantInformation", engine)

Use one of the below code format to create engine
from sqlalchemy import create_engine
# default
engine = create_engine('mysql://scott:tiger#localhost/foo')
# mysql-python
engine = create_engine('mysql+mysqldb://scott:tiger#localhost/foo')
# MySQL-connector-python
engine = create_engine('mysql+mysqlconnector://scott:tiger#localhost/foo')
# OurSQL
engine = create_engine('mysql+oursql://scott:tiger#localhost/foo')
# query
connection = engine.connect()
result = connection.execute("select username from users")
database name = foo, username = scott, password = tiger, host = localhost
Reference: http://docs.sqlalchemy.org/en/latest/dialects/mysql.html

'module' object is not callable with sqlalchemy

I'm totally new using sqlalchemy and postgresql. I read this tutorial to build the following piece of code :
import sqlalchemy
from sqlalchemy import create_engine
from sqlalchemy import engine
def connect(user, password, db, host='localhost', port=5432):
'''Returns a connection and a metadata object'''
# We connect with the help of the PostgreSQL URL
# postgresql://federer:grandestslam#localhost:5432/tennis
url = 'postgresql://{}:{}#{}:{}/{}'
url = url.format(user, password, host, port, db)
# The return value of create_engine() is our connection object
con = sqlalchemy.create_engine(url, client_encoding='utf8')
# We then bind the connection to MetaData()
meta = sqlalchemy.MetaData(bind=con, reflect=True)
return con, meta
con, meta = connect('federer', 'grandestslam', 'tennis')
con
engine('postgresql://federer:***#localhost:5432/tennis')
meta
MetaData(bind=Engine('postgresql://federer:***#localhost:5432/tennis'))
When running it I have this error :
File "test.py", line 22, in <module>
engine('postgresql://federer:***#localhost:5432/tennis')
TypeError: 'module' object is not callable
what should I do ? thanks !

So, your problem is happening because you've made this call:
from sqlalchemy import engine
And then you've used this later in the file:
engine('postgresql://federer:***#localhost:5432/tennis')
Strangely, in that section, you have some statements that are just con and meta with no assignments or calls or anything. I'm not sure what you're doing there. I would suggest that you check out SQLalchemy's page on engine and connection use to help get you sorted.
It will of course depend on exactly how you've set up your database. I used the declarative_base module in one of my projects, so my process of setting up a session to connect to my DB looks like this:
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
# Connect to Database and create database session
engine = create_engine('postgresql://catalog:catalog#localhost/menus')
Base.metadata.bind = engine
DBSession = sessionmaker(bind=engine)
session = DBSession()
And in my database setup file, I've assigned:
Base = declarative_base()
But you'll have to customize it a bit to your particular setup. I hope that helps.
Edit: I see now where those calls to con and meta were coming from, as well as your other confusing lines, it's part of the tutorial you linked to. What he was doing in that tutorial was using the Python interpreter in command line. I'll explain a few of the things he did there in the hope that it helps you some more. Lines beginning with >>> are what he enters in as commands. The other lines are the output he receives back.
>>> con, meta = connect('federer', 'grandestslam', 'tennis') # he creates the connection and meta objects
>>> con # now he calls the connection by itself to have it show that it's connected to his DB
Engine(postgresql://federer:***#localhost:5432/tennis)
>>> meta # here he calls his meta object to show how it, too, is connected
MetaData(bind=Engine(postgresql://federer:***#localhost:5432/tennis))

MySQL Connection not available when use SQLAlchemy(MySQL) and Flask

I'm getting this error sometime (sometime is ok, sometime is wrong):
sqlalchemy.exc.OperationalError: (OperationalError) MySQL Connection not available.
while using session.query
I'm writing a simple server with Flask and SQLAlchemy (MySQL). My app.py like this:
Session = sessionmaker(bind=engine)
session = Session()
#app.route('/foo')
def foo():
try:
session.query(Foo).all()
except Exception:
session.rollback()
Update
I also create new session in another file and call it in app.py
Session = sessionmaker(bind=engine)
session = Session()
def foo_helper(): #call in app.py
session.query(Something).all()
Update 2
My engine:
engine = create_engine('path')
How can I avoid that error?
Thank you!

Make sure the value of ‘pool_recycle option’ is less than your MYSQLs wait_timeout value when using SQLAlchemy ‘create_engine’ function.
engine = create_engine("mysql://username:password#localhost/myDatabase", pool_recycle=3600)
Try to use scoped_session to make your session:
from sqlalchemy.orm import scoped_session, sessionmaker
session = scoped_session(sessionmaker(autocommit=False, autoflush=False, bind=engine))
and close/remove your session after retrieving your data.
session.query(Foo).all()
session.close()

How do I connect as sysdba for oracle db using SQLALchemy

I am using sqlalchemy with flask
and I want to connect to oracle DB as sysdba
SQLALCHEMY_DATABASE_URI ='oracle+cx_oracle://sys:abc#DBNAME[mode=SYSDBA]'
This doesnt work and gives me a
from flask import Flask
from flask.ext.sqlalchemy import SQLAlchemy
app = Flask(__name__)
app.config.from_object('config')
db = SQLAlchemy(app)
from app import views,models
and I use this db object later. But I am not able to figure out how to write the
SQLALCHEMY_DATABASE_URI to login as sysdba
I also tried
CONN = cx_Oracle.connect('sys/abc', dsn='DBNAME', mode = cx_Oracle.SYSDBA)
SQLALCHEMY_DATABASE_URI = CONN
But that also doesnt work.
I get ORA-12154: TNS: could not resolve the connect identifier specified” .. also If I remove mode=SYSDBA I get ORA-28009 connection as SYS should be as SYSDBA

Your dsn parameter is wrong. You must also separate the user and password parameters. Try this (it's working for me):
dsn_tns = cx_Oracle.makedsn('host', port, 'sid')
CONN = cx_Oracle.connect('sys', 'abc', dsn_tns, mode=cx_Oracle.SYSDBA)
For more info see cx_Oracle.connect constructor.