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SPEAKER 1: Let's let our
user buy some stocks.

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The first thing that
you'll want to do in Buy

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is display a form where
the user will input

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the stock and the number of shares
that they want to buy of that stock.

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Then, checking that
everything is valid, you'll

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want to add that stock to the user's
portfolio and update their cash.

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So let's talk about the display form.

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Yet again, it's going
to be another template

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that we create where, within this form,
we'll ask for the symbol of the stock

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and the number of shares,
checking for valid input.

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From there, let's add the
stock to the user's portfolio.

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But we'll only want to allow them to
buy it if they can afford that stock.

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If I'm dealing with my
user with ID number one,

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then I could execute
the following SQL query,

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selecting the Cash column from the
user's table where ID equals one.

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From there, I can see whether
they can afford it or not.

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Now, looking at the structure
of the user's table,

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we only have three columns--

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user name, ID, and the
hash of their password.

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We don't have the capacity to
keep track of the user's purchase.

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So let's make a new SQL table.

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For this, we want to keep track of who
bought what at what price, and when.

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So make sure to use
the appropriate SQLite

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types when you're creating
this table, defining

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unique indices on any fields that
should be unique and non-unique for all

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of the others.

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Feel free to call your table
portfolio, transactions, history,

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or any other appropriate name.

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You could also create
two tables if you choose

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to structure your database that way.

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All right, now that we've added
the stock to the user's portfolio,

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let's make sure to subtract
the right amount of cash.

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Remember that a user's cash
is stored in the user's table.

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So if I'm again dealing with
my user with ID number one

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then I would execute this following
query, updating the user's table,

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setting the cash column
to cash minus $50,

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let's say, where that
user ID is equal to one.

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And with that, you've
bought your first stock.

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