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postgresqlsqlalchemypgadmin

PostgresSql Environment variable $DATABASE_URL not set, and no connect string given

I am seeing a connection error when i try to read data from postgressql in my jupyter notebook. The error suggests:

Connection info needed in SQLAlchemy format, example:
               postgresql://username:password@hostname/dbname
               or an existing connection: dict_keys([])

As far as i can see the example format matches with my connection string provided. I have also checked that i have updated version of sqlachemy. What am i missing ?

enter image description here

engine=create_engine(f'postgresql://postgres:root@localhost/GoldPrices')
engine.connect()

#To load ipython-sql
%load_ext sql

%sql postgresql://postgres:root@localhost/GoldPrices

postgresql

Solution

  • From here https://github.com/catherinedevlin/ipython-sql:

    Legacy project

    IPython-SQL's functionality and maintenance have been eclipsed by JupySQL, a fork maintained and developed by the Ploomber team. Future work will be directed into JupySQL - please file issues there, as well!

    So go here:

    https://jupysql.ploomber.io/en/latest/quick-start.html#

    and then:

    pip install jupysql

    With SQLAlchemy==2.0.23.

    Then:

    %load_ext sql
from sqlalchemy import create_engine
db_url = "postgresql://postgres:@localhost/test"
engine = create_engine(db_url)
%sql engine
%sql select * from cell_per

    Though if you want to stick with ipython-sql, per instructions here:

    https://github.com/catherinedevlin/ipython-sql

    Do the following:

    %load_ext sql
%%sql postgresql://postgres:@localhost/test
select * from cell_per