WEBVTT

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<v ->So let's go ahead and make the changes</v>

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to the database that we need to make.

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Let's start with our database changes in poll.py.

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We need get poll options and get poll.

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So I'm gonna go over to database.py down here.

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I'm gonna add a quick comment just to say polls,

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and then we're going to start creating our functions here.

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I'm actually going to move create poll up to the top.

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I'm gonna give you this file afterwards, by the way,

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so if you're a bit lost with these changes, don't worry.

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I'm gonna give you everything that we've changed over,

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and it's all in the e-book as well.

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So create poll is up here.

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We're gonna have get polls.

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We need one for getting a single poll,

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so we're gonna do get poll.

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Takes in a connection and a poll ID,

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and that should be an integer,

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and returns a poll, and then it just uses a connection

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with connection dot cursor as cursor,

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and execute.

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So cursor execute.

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We're gonna execute select poll,

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notice that doesn't exist, with poll ID.

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Then at the end we return cursor dot fetch one.

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Alright, so let's create select poll.

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Just like that, we're gonna select star from polls,

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where the ID is equal to the question mark.

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Or, actually, this should be percent S, my apologies.

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Still in SQLite mode.

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So there we have our query to select a single poll,

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and now we've got the get poll function there.

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Something important to note and that can be a bit confusing

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is this poll return here.

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Remember, this is the poll type that we defined,

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and it's not the poll class,

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because the database is still very much

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working with tuples and not with classes.

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That is what the model classes are for.

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We no longer need get poll details,

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but we do need get poll options,

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so we're going to change this into get poll options,

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and it does very much the same thing

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but now it returns a list of options.

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We do have to create that, and again,

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all it does is use the connection, use the cursor,

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and then it's gonna select poll options,

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not poll with options, passing in the poll ID

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and then fetch everything.

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We now have to go ahead and create these, too.

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So what we're gonna do is down here,

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we're gonna do option equal a tuple of INT S-T-R and INT.

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We no longer need poll with option,

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and we do need the query.

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So instead of select poll with options,

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we're just gonna do select poll options,

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and it's gonna be simpler.

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We just have to select star from options

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where poll ID is equal to that.

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So we'll do where poll ID is equal to that.

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We don't need to join anymore,

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and we can actually make this a single string.

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So you can see that by removing the join,

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this query and that return is now

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only going to return options.

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So when we use that in here, that is just going

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to give us the option data,

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and we are then passing that into the option constructor

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which gives us an option object,

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and that is what we're putting

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into our list that we return.

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So later on, app.py is going to be dealing

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with poll and option objects.

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So that's everything for the poll.py class.

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Now we can move onto option.py,

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make sure that we've got everything that we need

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from the database.

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So we've got add option and get option

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and get votes for option that we need to add.

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So let's go into database.py and add that.

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So here underneath get poll options

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I'm going to add another comment for options,

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and note that we don't really need a lot of these things

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so we're gonna be deleting them in a moment,

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but I'm gonna go ahead and do get option.

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That takes a connection and an option ID,

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which is an integer, and returns an option,

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and we also need add option, which takes a connection,

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option text, poll ID, and again,

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we're gonna do pass in there.

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Once we've got that, what else are we missing?

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Get votes for option.

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So we're gonna be adding that as well.

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So if we go over to database.py down here,

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we're gonna add a comment for votes

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and we're gonna do get votes for option.

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Takes in a connection and an option ID as well,

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and is gonna return a list of votes.

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Alright, what else do we need?

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We need add poll vote.

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So we're gonna make sure that that's there,

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and we can see it.

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It's down here, so all we have to do now

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is delete the rest.

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We're no longer gonna use the database

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to get a random poll vote, and we're no longer

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gonna get poll and vote results together,

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so we can get rid of those.

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While I'm here I'm noticing this red underline here.

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This should just be returning a poll and not a list of polls

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so we actually have to change this query.

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Instead of select latest poll with options,

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now we're just gonna change this to select latest poll,

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just like that, and the query has to change slightly.

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We simply find a bit in that it no longer needs the join.

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Alright, let's make sure to use that down here.

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Cool, now let's go and implement

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the get option and add option functions.

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I've gone ahead and written these in.

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We've got select option being called here

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to fetch one individual option,

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and add option just uses the insert option query

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that already existed, so all we have to do

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is go up here and find a way to select that single option,

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which we know how to do.

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We can just do select option equal

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select star from options where ID equal percent S.

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Finally, for get votes for option,

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all we have to do, again, is call the appropriate query.

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So that's select vote for options.

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That doesn't exist yet, but we can make it.

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We'll do select votes for option equal

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select star from votes where option ID equal percent S.

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So select poll vote details is no longer necessary,

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and you can start to see, the other thing we don't need

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is, of course, select random vote.

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We've got rid of that function,

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so we're gonna get rid of that query,

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and we're gonna calculate the random votes using Python.

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And something else we don't need

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is the poll results data type here,

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so I'm just gonna get rid of that.

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Something I forgot to change here when creating polls

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is that we no longer need to pass in

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a list of options in here, and indeed,

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the create poll only needs to grab

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the insert poll return ID.

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So what we're gonna do is we're going to delete that

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and then return poll ID.

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Now when we call this, we're gonna be doing that

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from poll.py, so do make sure that we fix this.

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Here we need to pass in a connection and that's about it.

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In option.py I actually forgot the same thing,

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so make sure to pass the connection in there.

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Just pay attention to the PyCharm type hints there

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that I clearly didn't,

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and then let's go over to add option here

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and we're gonna make sure that we're returning

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the ID that the option method needs.

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So we're gonna add returning ID here to the query name,

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and then we're gonna do option ID

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is equal to cursor dot fetch one zero,

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and we're gonna return option ID.

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Then I'm gonna copy that, go up to the top,

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and just rename this here.

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I'm actually gonna rename it to match poll there,

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so just return ID there.

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The values are gonna be percent S, percent S,

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and returning ID.

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Now let's copy that and go back down.

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Make sure that this is matching.

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It's good to have consistency there in the code.

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Alright, that's all the changes we have to make.

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Now we're ready to go over to app.py.

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So I'll see you in the next video for that.