ruby_mysql.rb

require 'mysql2'

def my_db
  return Mysql2::Client.new(
    :host      => '127.0.0.1',
    :username  => 'root',
    :password  => 'password',
    :encoding  => 'utf8mb4',
    :database  => 'medium_story',
    :ssl_mode  => 'disabled',
    :reconnect => true
  )
end

def get_contacts
  a=Array.new
  db=my_db()
  results=db.query("SELECT id,name,address,phone FROM contacts")
  results.each do|row|
    a.push(row)
  end
  db.close
  return a
end

def insert_contact(name,address,phone)
  db=my_db
  sql=db.prepare("
                 INSERT INTO contacts(name,address,phone)
                 VALUES (?,?,?)
                 ")
  sql.execute(name,address,phone)
  db.close
end

insert_contact('Bill Gates','Seattle','+1 206-336-3767')
insert_contact('Elon Musk','California','+1 408-249-2815')

cs=get_contacts()
for z in 0..cs.length-1
  c=cs[z]
  puts "%s\t%s\t%s\t%s" % [c['id'],c['name'],c['address'],c['phone']]
end