Building Data-Driven Web Apps with Flask and SQLAlchemy Transcripts
Chapter: Course conclusion
Lecture: Querying data
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We saw how nice and powerful it was
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to model our database in terms of Python classes
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and then use SQLAlchemy to run queries against that.
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So, here we have a find_account_by_login.
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And we're going to get an email and a password.
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And in this in case, we're not doing the path load stuff
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probably not the way we should do it
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but just in this little example we can directly
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compare the hashes.
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So we go and create our session.
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Remember, we use the unit of work design pattern.
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So we do that by creating the session
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and then we go to the session
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create a query based on a class
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so we're creating an account query.
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Then we say we'd like to do a filter
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where the class.email == the passed-in email
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and then we're chaining on an "and" condition
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another filter where the password hash equals the hash.
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What we'll see at the bottom is something roughly equivalent
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to select * from account
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where account.email equals what were
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push parameter, and account.password_hash is second.
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And the params are michael@talkpython.fm
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and my favorite password, abc.
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We thought it's actually a little bit more complicated.
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It states out all the columns and whatnot
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but that's roughly the idea
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and this is how we use SQLAlchemy.
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Highly recommended.
