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docs/mapping-and-entities.md

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+# Mapping and Entities
+
+DynamORM supports attribute-driven mapping and entity lifecycle helpers.
+
+## Mapping Attributes
+
+## `TableAttribute`
+
+```csharp
+[Table(Name = "users", Owner = "dbo", Override = true)]
+public class User
+{
+    // ...
+}
+```
+
+- `Name`: table name override.
+- `Owner`: schema/owner segment.
+- `Override`: prefer attribute schema info over provider schema.
+
+## `ColumnAttribute`
+
+```csharp
+public class User
+{
+    [Column("id", isKey: true)]
+    public int Id { get; set; }
+
+    [Column("email")]
+    public string Email { get; set; }
+}
+```
+
+Important flags:
+
+- `IsKey`
+- `AllowNull`
+- `IsNoInsert`
+- `IsNoUpdate`
+- `Type`, `Size`, `Precision`, `Scale`
+
+## Ignore Fields
+
+Use `IgnoreAttribute` to skip properties in mapper-driven workflows.
+
+## Validation
+
+`RequiredAttribute` can define value rules.
+
+```csharp
+public class Profile
+{
+    [Required(1f, 10f)]
+    public int Rank { get; set; }
+
+    [Required(2, true)]
+    [Required(7, 18, ElementRequirement = true)]
+    public decimal[] Scores { get; set; }
+}
+
+var issues = DynamicMapperCache.GetMapper<Profile>().ValidateObject(profile);
+```
+
+Validation scenarios are verified in `DynamORM.Tests/Helpers/Validation/ObjectValidationTest.cs`.
+
+## `DynamicEntityBase`
+
+`DynamicEntityBase` tracks state and changed fields.
+
+```csharp
+public class UserEntity : DynamicEntityBase
+{
+    [Column("id", true)]
+    public int Id { get; set; }
+
+    [Column("first")]
+    public string First { get; set; }
+}
+```
+
+Available behaviors:
+
+- `Validate()`
+- `Insert(db)`
+- `Update(db)`
+- `Delete(db)`
+- `Refresh(db)`
+- `Save(db)` driven by `DynamicEntityState`
+
+## Repository Base
+
+`DynamicRepositoryBase<T>` provides common operations:
+
+- `GetAll()`
+- `GetByQuery(...)`
+- `Insert(...)`
+- `Update(...)`
+- `Delete(...)`
+- `Save(...)`
+
+It ensures query/table compatibility for `T` unless explicitly bypassed.