Your data access code will not compile without an existing database - unless you drown it (or not therefore, it is likely that the database will be the first.
But it’s a bad idea to do whole pieces of the application in isolation. Ideally, you should design and create system slides — databases and applications — hand in hand. These sliders should be a cohesive subset of the functionality, possibly smaller than the subsystems. Inevitably, the operation of coding screens and business rules will cause problems in the data model. Therefore, it is good to have a data model or database administrators who are happy to work gradually with the developers.
change
Stephanie makes an extremely pertinent point:
"The main tables that your application data is saved really cannot be piecemealed. Most of the data is known when you start the project. It has the form you need to find it."
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