Add On Delete/Update Constraint

GORM-V2-Release-Note-Draft-CN.md

@@ -12,7 +12,7 @@ GORM 2.0 现处于公测阶段，已部署于多个用户的生产服务环境
 * 代码模块化
 * Context、批量插入、Prepared Statment、DryRun 模式、Join Preload, Find 到 Map, FindInBatches 支持
 * SavePoint/RollbackTo/Nested Transaction 支持
-* 关联关系优化，多对多中间表替换优化，Association 模式对批量数据支持及优化
+* 关联关系优化 (On Delete/Update)，多对多中间表替换优化，Association 模式对批量数据支持及优化
 * SQL Builder 优化, Upsert, Locking, Optimizer/Index/Comment Hints 支持
 * 插入时间、更新时间可支持多个字段，加入了对 unix (nano) second 的支持
 * 字段多重权限支持：只读、只允许创建、只允许更新、只写、完全忽略
@@ -255,6 +255,22 @@ type Blog struct {
 }
 ```
 
+#### 关联 On Delete/Update 支持
+
+```go
+type Profile struct {
+  gorm.Model
+  Refer string
+  Name  string
+}
+
+type User struct {
+  gorm.Model
+  Profile   Profile `gorm:"Constraint:OnUpdate:CASCADE,OnDelete:CASCADE;"`
+  ProfileID int
+}
+```
+
 ### 多对多中间表替换优化
 
 可以更简单的来设置 `Many2Many` 的 `JoinTable`，替换后的 `JoinTable` 可获得普通模型的全部功能，例如 `Soft Delete`，`Hooks` 等功能支持，也可以添加更多字段

GORM-V2-Release-Note-Draft.md

@@ -12,7 +12,7 @@ GORM 2.0 is not yet released, currently, in the public beta stage, it has been u
 * Modularity
 * Context, Batch Insert, Prepared Statment, DryRun Mode, Join Preload, Find To Map, FindInBatches
 * SavePoint/RollbackTo/Nested Transaction Support
-* Association improvements, Modify Join Table for Many2Many, Association Mode for batch data
+* Association improvements (On Delete/Update), Modify Join Table for Many2Many, Association Mode for batch data
 * SQL Builder, Upsert, Locking, Optimizer/Index/Comment Hints supports
 * Multiple fields support for auto creating/updating time, which also support unix (nano) seconds
 * Field permissions support: readonly, writeonly, createonly, updateonly, ignored
@@ -256,6 +256,22 @@ type Blog struct {
 }
 ```
 
+#### Association On Delete/Update Support
+
+```go
+type Profile struct {
+  gorm.Model
+  Refer string
+  Name  string
+}
+
+type User struct {
+  gorm.Model
+  Profile   Profile `gorm:"Constraint:OnUpdate:CASCADE,OnDelete:CASCADE;"`
+  ProfileID int
+}
+```
+
 ### Modify Join Table for Many2Many
 
 Easier to setup Many2Many's `JoinTable`，the `JoinTable` can be a full-featured model, like having `Soft Delete`，`Hooks` supports, and define more fields