From d2e526bc2d4576c20ba60b98d09251be5b469d8c Mon Sep 17 00:00:00 2001
From: Vladimir Garvardt <vgarvardt@gmail.com>
Date: Thu, 12 Jun 2014 00:51:27 +0400
Subject: [PATCH] db.Create() for force insert with predefined primary key

---
 README.md          |  6 ++++++
 callback_create.go | 11 +++++++++--
 main.go            |  5 +++++
 main_test.go       | 14 ++++++++++++++
 4 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index ee80c444..d29a5edc 100644
--- a/README.md
+++ b/README.md
@@ -237,6 +237,12 @@ db.Save(&user)
 //// COMMIT;
 ```
 
+### Create With Predefined Primary key
+
+```go
+db.Create(&User{Id: 999, Name: "user 999"})
+```
+
 ## Query
 
 ```go
diff --git a/callback_create.go b/callback_create.go
index 8276f0d2..1cf4fcb4 100644
--- a/callback_create.go
+++ b/callback_create.go
@@ -26,8 +26,15 @@ func Create(scope *Scope) {
 		// set create sql
 		var sqls, columns []string
 
+		primaryKeyPredefined := false
 		for _, field := range scope.Fields() {
-			if field.DBName != scope.PrimaryKey() && len(field.SqlTag) > 0 && !field.IsIgnored {
+			if field.DBName == scope.PrimaryKey() {
+				primaryKeyValue := fmt.Sprintf("%v", field.Value)
+				if primaryKeyValue != "" && primaryKeyValue != "0" {
+					primaryKeyPredefined = true
+				}
+			}
+			if len(field.SqlTag) > 0 && !field.IsIgnored && (field.DBName != scope.PrimaryKey() || primaryKeyPredefined) {
 				columns = append(columns, scope.Quote(field.DBName))
 				sqls = append(sqls, scope.AddToVars(field.Value))
 			}
@@ -65,7 +72,7 @@ func Create(scope *Scope) {
 			}
 		}
 
-		if !scope.HasError() {
+		if !scope.HasError() && !primaryKeyPredefined {
 			scope.SetColumn(scope.PrimaryKey(), id)
 		}
 	}
diff --git a/main.go b/main.go
index e3fd9fe2..17e3246c 100644
--- a/main.go
+++ b/main.go
@@ -214,6 +214,11 @@ func (s *DB) Save(value interface{}) *DB {
 	}
 }
 
+func (s *DB) Create(value interface{}) *DB {
+	scope := s.clone().NewScope(value)
+	return scope.callCallbacks(s.parent.callback.creates).db
+}
+
 func (s *DB) Delete(value interface{}) *DB {
 	return s.clone().NewScope(value).callCallbacks(s.parent.callback.deletes).db
 }
diff --git a/main_test.go b/main_test.go
index 6d0d17e1..46d6e6e4 100644
--- a/main_test.go
+++ b/main_test.go
@@ -2083,3 +2083,17 @@ func TestHstore(t *testing.T) {
 	}
 
 }
+
+func TestCreate(t *testing.T) {
+	if err := db.Create(&UserCompany{Id: 10, UserId: 1, CompanyId: 1}).Error; err != nil {
+		t.Error("Should be able to create record with predefined Id")
+	}
+
+	if db.First(&UserCompany{}, 10).RecordNotFound() {
+		t.Error("Record created with predefined primary key not found")
+	}
+
+	if err := db.Create(&UserCompany{Id: 10, UserId: 10, CompanyId: 10}).Error; err == nil {
+		t.Error("Should not be able to create record with predefined duplicate Id")
+	}
+}