How would you map a value object in modern EF Core, and when would you choose a complex type, an owned entity, or a regular entity?

Owned entities, complex types, and value objects in EF Core

Chooses between EF Core complex types, owned entities, and regular entities from value semantics, identity, ownership, querying, and storage needs.

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TL;DR

For a value such as Address or Money that has no identity outside its owner, I usually start with an EF Core complex type. It keeps the domain concept grouped while mapping its properties into the owner table or, where supported, a JSON column. I use an owned entity when I specifically need ownership modeled with entity semantics, and a regular entity when the value has its own identity, lifecycle, or references. The CLR type should still enforce invariants rather than becoming a loose bag of mapped properties.

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Value semantics, EF Core complex types, owned entity identity, ownership, table and JSON mapping, invariants, migrations, and query behavior.

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Why this question matters
Modern EF Core offers more than one way to persist an identity-free domain value. The right mapping depends on whether the type truly has value semantics, needs entity behavior, or should have independent identity and lifecycle.
For a value such as Address or Money that has no identity outside its owner, I usually start with an EF Core complex type. It keeps the domain concept grouped while mapping its properties into the owner table or, where supported, a JSON column. I use an owned entity when I specifically need ownership modeled with entity semantics, and a regular entity when the value has its own identity, lifecycle, or references. The CLR type should still enforce invariants rather than becoming a loose bag of mapped properties.
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Treating EF Core owned types and value objects as a syntax detail instead of a production behavior.
Not checking generated SQL, query plans, or actual data volume.
Testing only with tiny local data and assuming production will behave the same.
Fixing symptoms with caching, timeouts, or retries before understanding the data-access cause.

How would you map a value object in modern EF Core, and when would you choose a complex type, an owned entity, or a regular entity?

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