alt Hacker NewsI wouldn't give too much credit to rules like this. Data structures are often created with an approach in mind. You can't design a data structure without knowing how you will use it.
If anything it's the other way round, if you're not talking about business domain modeling (where data structures first is a valid approach).
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To elaborate on @jeswin's point above (IDK why it got downvoted)... a data structure is basically like a cache for the processing algorithm. The business logic and algorithm needs will dictate what details can be computed on-the-fly -vs- pre-generated and stored (be it RAM or disk). Eg: if you're going to be searching a lot then it makes sense to augment the database with some kind of "index" for fast lookup. Or if you are repeatedly going to be pllotting some derived quantity then maybe it makes sense to derive that once and store with the struct.
It's not enough for a data structure to represent the "fundamental" degrees of freedom needed to model the situation; the algorithmic needs (vis-a-vis the available resources) most definitely matter a lot.
If you don't know enough to design a data structure, requirements are missing and someone talking to the client is dropping the ball big time.
> If anything it's the other way round, if you're not talking about business domain modeling (where data structures first is a valid approach).
And even there, the data models usually come about to make specific business processes easier (or even possible). An Order Summary is structured a specific way to allow both the Fulfilment and Invoicing processes possible, which feed down into Payment and Collections processes (and related artefacts).