Demonstrate bad Where clause

main_test.go

@@ -2,19 +2,37 @@ package main
 
 import (
 	"testing"
+
+	"github.com/gofrs/uuid"
 )
 
 // GORM_REPO: https://github.com/go-gorm/gorm.git
 // GORM_BRANCH: master
 // TEST_DRIVERS: sqlite, mysql, postgres, sqlserver
 
 func TestGORM(t *testing.T) {
-	user := User{Name: "jinzhu"}
+	uuid1, _ := uuid.NewV4()
+	user := User{Name: "jinzhu", UserID: uuid1}
+	uuid2, _ := uuid.NewV4()
+	user2 := User{Name: "philicious", UserID: uuid2}
 
 	DB.Create(&user)
+	DB.Create(&user2)
+
+	var resultGood []User
+	_ = DB.Debug().Where(&User{UserID: uuid1}).Find(&resultGood)
+	// resulting query: SELECT * FROM `users` WHERE `users`.`user_id` = "a543742b-9fe4-49ec-9226-e980be5669a8" AND `users`.`deleted_at` IS NULL
+
+	if len(resultGood) > 1 {
+		t.Errorf("should only find a single user")
+	}
+
+	var resultBad []User
+	uuidNull, _ := uuid.FromString("00000000-0000-0000-0000-000000000000") // same as using uuid.Nil or uuid.FromStringOrNil(uuidString)
+	_ = DB.Debug().Where(&User{UserID: uuidNull}).Find(&resultBad)
+	// resulting query: SELECT * FROM `users` WHERE `users`.`deleted_at` IS NULL
 
-	var result User
-	if err := DB.First(&result, user.ID).Error; err != nil {
-		t.Errorf("Failed, got error: %v", err)
+	if len(resultBad) > 0 {
+		t.Errorf("should NOT find a user")
 	}
 }

models.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"time"
 
+	"github.com/gofrs/uuid"
 	"gorm.io/gorm"
 )
 
@@ -13,6 +14,7 @@ import (
 // His pet also has one Toy (has one - polymorphic)
 type User struct {
 	gorm.Model
+	UserID    uuid.UUID
 	Name      string
 	Age       uint
 	Birthday  *time.Time