app.py

import psycopg2
import pandas.io.sql as sqlio
import pandas as pd
import dash
from dash import dcc
from dash import html
import plotly.express as px

app = dash.Dash(__name__)

# Connect to an existing database
conn = psycopg2.connect("dbname=materialize user=materialize port=6875 host=localhost")

sql = "select * from sales_by_customer;"
df = pd.read_sql_query(sql, conn)

fig = px.bar(df, x="customer_id", y="total_order_value")


# Main UI scaffolding
app.layout = html.Div(children=[
    html.H1(children='Sales by customer'),

    html.Div(children='''
        Dash: A web application framework for your data.
    '''),

    dcc.Graph(
        id='bar-chart',
        figure=fig
    )
])

if __name__ == '__main__':
    app.run_server(debug=True)

conn = None