refacto: add polymorphism informations (#759)

* refacto: add polymorphism informations

* fix: doc

pages/_data/sidebar.yml

@@ -15,6 +15,7 @@ docs:
     has_one: has_one.html
     has_many: has_many.html
     many_to_many: many_to_many.html
+    polymorphism: polymorphism.html
     association_mode: associations.html
     preload: preload.html
   tutorials:

pages/docs/has_many.md

@@ -77,49 +77,6 @@ type CreditCard struct {
 }
 ```
 
-## Polymorphism Association
-
-GORM supports polymorphism association for `has one` and `has many`, it will save owned entity's table name into polymorphic type's field, primary key value into the polymorphic field
-
-```go
-type Dog struct {
-  ID   int
-  Name string
-  Toys []Toy `gorm:"polymorphic:Owner;"`
-}
-
-type Toy struct {
-  ID        int
-  Name      string
-  OwnerID   int
-  OwnerType string
-}
-
-db.Create(&Dog{Name: "dog1", Toys: []Toy{{Name: "toy1"}, {Name: "toy2"}}})
-// INSERT INTO `dogs` (`name`) VALUES ("dog1")
-// INSERT INTO `toys` (`name`,`owner_id`,`owner_type`) VALUES ("toy1","1","dogs"), ("toy2","1","dogs")
-```
-
-You can change the polymorphic type value with tag `polymorphicValue`, for example:
-
-```go
-type Dog struct {
-  ID   int
-  Name string
-  Toys []Toy `gorm:"polymorphic:Owner;polymorphicValue:master"`
-}
-
-type Toy struct {
-  ID        int
-  Name      string
-  OwnerID   int
-  OwnerType string
-}
-
-db.Create(&Dog{Name: "dog1", Toys: []Toy{{Name: "toy1"}, {Name: "toy2"}}})
-// INSERT INTO `dogs` (`name`) VALUES ("dog1")
-// INSERT INTO `toys` (`name`,`owner_id`,`owner_type`) VALUES ("toy1","1","master"), ("toy2","1","master")
-```
 
 ## CRUD with Has Many
 

pages/docs/has_one.md

@@ -78,56 +78,6 @@ type CreditCard struct {
 }
 ```
 
-## Polymorphism Association
-
-GORM supports polymorphism association for `has one` and `has many`, it will save owned entity's table name into polymorphic type's field, primary key into the polymorphic field
-
-```go
-type Cat struct {
-  ID    int
-  Name  string
-  Toy   Toy `gorm:"polymorphic:Owner;"`
-}
-
-type Dog struct {
-  ID   int
-  Name string
-  Toy  Toy `gorm:"polymorphic:Owner;"`
-}
-
-type Toy struct {
-  ID        int
-  Name      string
-  OwnerID   int
-  OwnerType string
-}
-
-db.Create(&Dog{Name: "dog1", Toy: Toy{Name: "toy1"}})
-// INSERT INTO `dogs` (`name`) VALUES ("dog1")
-// INSERT INTO `toys` (`name`,`owner_id`,`owner_type`) VALUES ("toy1","1","dogs")
-```
-
-You can change the polymorphic type value with tag `polymorphicValue`, for example:
-
-```go
-type Dog struct {
-  ID   int
-  Name string
-  Toy  Toy `gorm:"polymorphic:Owner;polymorphicValue:master"`
-}
-
-type Toy struct {
-  ID        int
-  Name      string
-  OwnerID   int
-  OwnerType string
-}
-
-db.Create(&Dog{Name: "dog1", Toy: Toy{Name: "toy1"}})
-// INSERT INTO `dogs` (`name`) VALUES ("dog1")
-// INSERT INTO `toys` (`name`,`owner_id`,`owner_type`) VALUES ("toy1","1","master")
-```
-
 ## CRUD with Has One
 
 Please checkout [Association Mode](associations.html#Association-Mode) for working with `has one` relations

pages/docs/polymorphism.md

@@ -0,0 +1,58 @@
+---
+title: Polymorphism
+layout: Page
+---
+
+## Polymorphism Association
+
+GORM supports polymorphism association for `has one` and `has many`, it will save owned entity's table name into polymorphic type's field, primary key value into the polymorphic field
+
+By default `polymorphic:<value>` will prefix the column type and column id with `<value>`. 
+The value will be the table name pluralized. 
+
+```go
+type Dog struct {
+  ID   int
+  Name string
+  Toys []Toy `gorm:"polymorphic:Owner;"`
+}
+
+type Toy struct {
+  ID        int
+  Name      string
+  OwnerID   int
+  OwnerType string
+}
+
+db.Create(&Dog{Name: "dog1", Toys: []Toy{{Name: "toy1"}, {Name: "toy2"}}})
+// INSERT INTO `dogs` (`name`) VALUES ("dog1")
+// INSERT INTO `toys` (`name`,`owner_id`,`owner_type`) VALUES ("toy1",1,"dogs"), ("toy2",1,"dogs")
+```
+
+
+You can specify polymorphism properties separately using the following GORM tags:
+
+- `polymorphicType`: Specifies the column type.
+- `polymorphicId`: Specifies the column ID.
+- `polymorphicValue`: Specifies the value of the type.
+
+```go
+type Dog struct {
+  ID   int
+  Name string
+  Toys Toy `gorm:"polymorphicType:Kind;polymorphicId:OwnerID;polymorphicValue:master"`
+}
+
+type Toy struct {
+  ID        int
+  Name      string
+  OwnerID   int
+  Kind      string
+}
+
+db.Create(&Dog{Name: "dog1", Toys: []Toy{{Name: "toy1"}, {Name: "toy2"}}})
+// INSERT INTO `dogs` (`name`) VALUES ("dog1")
+// INSERT INTO `toys` (`name`,`owner_id`,`kind`) VALUES ("toy1",1,"master"), ("toy2",1,"master")
+```
+
+In these examples, we've used a has-many relationship, but the same principles apply to has-one relationships.

themes/navy/languages/en.yml

@@ -40,6 +40,7 @@ sidebar:
     belongs_to: Belongs To
     has_one: Has One
     has_many: Has Many
+    polymorphism: Polymorphism
     many_to_many: Many To Many
     association_mode: Association Mode
     preload: Preloading (Eager Loading)