dump csv from sqlalchemy

Question

For some reason, I want to dump a table from a database (sqlite3) in the form of a csv file. I\'m using a python script with elixir (based on sqlalchemy) to modify the datab

Answer 1

I know this is old, but i just had this problem and this is how i solved it

from sqlalchemy import create_engine

basedir = os.path.abspath(os.path.dirname(__file__))
sql_engine = create_engine(os.path.join('sqlite:///' + os.path.join(basedir, 'single_file_app.db')), echo=False)
results = pd.read_sql_query('select * from users',sql_engine)
results.to_csv(os.path.join(basedir, 'mydump2.csv'),index=False,sep=";")

Answer 2

In a modular way: an example using slqalchemy with automap and mysql.

database.py:

from sqlalchemy.ext.automap import automap_base
from sqlalchemy.orm import Session
from sqlalchemy import create_engine

Base = automap_base()

engine = create_engine('mysql://user:pass@localhost:3306/database_name', echo=True)

Base.prepare(engine, reflect=True)

# Map the tables
State = Base.classes.states

session = Session(engine, autoflush=False)

export_to_csv.py:

from databases import *
import csv

def export():

    q = session.query(State)

    file = './data/states.csv'

    with open(file, 'w') as csvfile:
        outcsv = csv.writer(csvfile, delimiter=',',quotechar='"', quoting = csv.QUOTE_MINIMAL)

        header = State.__table__.columns.keys()

        outcsv.writerow(header)     

        for record in q.all():
            outcsv.writerow([getattr(record, c) for c in header ])

if __name__ == "__main__":
    export()

Results:

name,abv,country,is_state,is_lower48,slug,latitude,longitude,population,area Alaska,AK,US,y,n,alaska,61.370716,-152.404419,710231,571951.25 Alabama,AL,US,y,y,alabama,32.806671,-86.79113,4779736,50744.0 Arkansas,AR,US,y,y,arkansas,34.969704,-92.373123,2915918,52068.17 Arizona,AZ,US,y,y,arizona,33.729759,-111.431221,6392017,113634.57 California,CA,US,y,y,california,36.116203,-119.681564,37253956,155939.52 Colorado,CO,US,y,y,colorado,39.059811,-105.311104,5029196,103717.53 Connecticut,CT,US,y,y,connecticut,41.597782,-72.755371,3574097,4844.8 District of Columbia,DC,US,n,n,district-of-columbia,38.897438,-77.026817,601723,68.34 Delaware,DE,US,y,y,delaware,39.318523,-75.507141,897934,1953.56 Florida,FL,US,y,y,florida,27.766279,-81.686783,18801310,53926.82 Georgia,GA,US,y,y,georgia,33.040619,-83.643074,9687653,57906.14