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Delivery estimates: postal zones

Experiment #8026th March, 2021by Joshua Nussbaum

In the previous experiment, I created a database to store delivery estimates.

In the sql, I loading the db with some countries and states, but I couldnt load the postal_codes table because there are 33,000 postal codes in the USA, and that’s too much data to send to the server.

So I wrote a script to do it, using the supabase API client.

The script parses a CSV files I found on the web, and inserts it into the DB (see video below).


import fs from 'fs'
import { createClient } from '@supabase/supabase-js'

const supabase = createClient('<supabase-url>', '<supabase-api-key>')
const path = './uszips.csv'
const data = await fs.promises.readFile(path, 'utf8')

const { data: rows } = await supabase

const subdivisions = {}

rows.forEach(row => {
  subdivisions[row.code] = row

data.split('\n').forEach(async ( line, index ) => {
  if (index == 0) return
  if (line.trim() == '') return

  const cells = line.split(',')

  let code = cells[0]
  const lat = cells[1]
  const lng = cells[2]
  const municipality = cells[3]
  const state = cells[4]
  const geog = `POINT(${lat} ${lng})`
  const subdivision = subdivisions[state]

  if (!subdivision) {
    console.log(`${state} is not defined`)

  if (code.length == 3) code = '0' + code
  if (code.length == 4) code = '0' + code

  const row = {
    country_id: subdivision.country_id,
    subdivision_id: subdivision.id,

  const {data, error} = await supabase.from('postal_codes').insert([row])
  console.log({data, error})


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