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Chapter: Appendix: Using SQLAlchemy
Lecture: Concept: Database updates
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In order to update existing data
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we start like we always do, we get a session.
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And then we retrieve one or more records form the database.
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Here we're just getting one package.
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When I get this package back, and if we make changes to it
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so we set the author value to a new name
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we set the author email to a new email
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SQLAlchemy will track within the session that
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that record is dirty and it needs to be updated
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because we've changed some fields.
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And then, when we're ready to actually save it
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push all the changes back.
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I could apply this to as many entities as we'd like
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it doesn't have to just be one.
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Then we're going to commit the unit of work
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and it's going to look at the changes
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do all the changes in a single transaction
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back to the database.
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We use the unit of work to do our updates
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just like we do the inserts.