{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Create A Database\n",
    "\n",
    "For this tutorial, we'll use the [SQLAlchemy](http://www.sqlalchemy.org/) Python library to communicate with a database.\n",
    "\n",
    "Let's import it:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import sqlalchemy as sa"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "SQLAlchemy uses an \"engine\" object to interact with a database.\n",
    "\n",
    "To create an engine, we first need to choose a Database Management System (DBMS). We'll use [SQLite](https://sqlite.org/index.html) as our DBMS.\n",
    "\n",
    "Next, we have to define a connection URL. The URL tells SQLAlchemy which DBMS we have chosen and how to connect to our database.\n",
    "\n",
    "SQLite uses a single file for each database and the structure of the URL we need for SQLAlchemy is:\n",
    "\n",
    "```\n",
    "sqlite:///<path to the database file>\n",
    "```\n",
    "\n",
    "Our example database will contain data about High Altitude Balloon flights. Let's name our database file ```flight.db``` and create an engine object for it:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [],
   "source": [
    "engine = sa.create_engine('sqlite:///flight.db')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "We can now connect to our database using the ```connect()``` method of our engine.\n",
    "\n",
    "SQLAlchemy will look for the file we specified in our URL and establish a connection to our database. If the file doesn't exist, sqlalchemy will create it and then make the connection."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "connection = engine.connect()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "You should now be able to see a new 'flight.db' file in the same directory as this notebook.\n",
    "\n",
    "If you opted to [run the code on your own computer](http://owencampbell.me.uk/pages/howto#howto-local) and also installed the graphical tool, you can also now start that program and open your new 'flight.db' file."
   ]
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python [conda env:sql_python_tutorial]",
   "language": "python",
   "name": "conda-env-sql_python_tutorial-py"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.6.5"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 2
}