business-logic-entry-point-repository-operations
Repository Operations for Business Logic Entry Points
Goal
Repository interfaces must expose a standard set of operations with clear naming, explicit intent, predictable return types, and a strict error model.
Each operation must make its purpose unambiguous. A caller reading the repository interface must know immediately whether it is creating a new entity, updating an existing one, retrieving zero-or-one by identity or unique key, retrieving zero-or-many by criteria, performing a dynamic listing, counting matches, asking whether something exists, or deleting by identity.
The operation set is organized in two families:
- Entity fetch family (
findBy*,findManyBy*,search) — returns domain entities. - Aggregation family (
countBy*,existsBy*,existManyBy*) — returns scalars (number, boolean) computed over the same predicates.
Two cross-cutting rules apply to every operation:
- Domain outcomes are valid return values, never errors. Not found, empty list, zero count, false existence — all are valid results. Errors are reserved for infrastructure failures.
saveis forbidden. Always distinguish betweencreateandupdateexplicitly so the caller's intent is never ambiguous.
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