#100DaysOfWeb in Python Transcripts
Chapter: Days 33-36: Database access with SQLAlchemy
Lecture: Importing starter data
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0:00
So, we think we have our data access layer working but we have no data. We can't really test it. So, let's go and add one more file.
0:08
And this one I'm going to drop in and just talk you through because it's super tedious to write.
0:12
So, what this is going to do is it's going to import data only if those particular tables are empty. So, it's going to import only the user's table
0:22
if there's no users, or the scooters if there's no scooters. So, let's just look at the scooter one. So, just like before, we create a session
0:28
and it does this check, this count to see if there are any scooters available. If they are, it must have pre-populated it.
0:35
We don't need to worry about it. Otherwise, it's going to have some models some random VIN values it can use and get all the locations
0:43
so that it can then use those to populate with. Then we're going to go and add 20 scooters here, 21 scooters. And it just randomly fills out the values
0:53
randomly generates a VIN number, randomly picks a location and adds it and then commit to all those. Same for all the others.
0:59
Right here you can see it's going to get the default user as well and create a second user so we have more than one.
1:06
I'm going to just delete this one more time so we start over. Now let's go to our program. And notice this part was still missing.
1:14
So, we'll say import data import if empty, and we delete this. Okay, so everything should be up and running.
1:23
Let's try to run this and see if we now have data. It didn't crash, so that's quite exciting. So, here you can see we have our scooters.
1:31
They all got created with their IDs and their VIN numbers and their versions, and their various battery levels. Some of them are checked out for rental
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because you can see their locations are null. These, the ones that have locations, they are checked in. Their batteries are charged up
1:46
and they're waiting to be rented. Looks like that's working. And it turns out the other ones are all good as well.
1:51
So the final thing to do before our app is entirely done is just implement these little functions.
1:58
That might sound hard, but it actually is pretty easy because we already wrote the data access stuff. We just have to do the reporting.