Add QueryExpr, thanks @ManReinsp for PR #1548

create_test.go

@@ -68,11 +68,11 @@ func TestCreateWithExistingTimestamp(t *testing.T) {
 	user.UpdatedAt = timeA
 	DB.Save(&user)
 
-	if user.CreatedAt.Format(time.RFC3339) != timeA.Format(time.RFC3339) {
+	if user.CreatedAt.UTC().Format(time.RFC3339) != timeA.UTC().Format(time.RFC3339) {
 		t.Errorf("CreatedAt should not be changed")
 	}
 
-	if user.UpdatedAt.Format(time.RFC3339) != timeA.Format(time.RFC3339) {
+	if user.UpdatedAt.UTC().Format(time.RFC3339) != timeA.UTC().Format(time.RFC3339) {
 		t.Errorf("UpdatedAt should not be changed")
 	}
 

main.go

@@ -168,6 +168,15 @@ func (s *DB) NewScope(value interface{}) *Scope {
 	return &Scope{db: dbClone, Search: dbClone.search.clone(), Value: value}
 }
 
+// QueryExpr returns the query as expr object
+func (s *DB) QueryExpr() *expr {
+	scope := s.NewScope(s.Value)
+	scope.InstanceSet("skip_bindvar", true)
+	scope.prepareQuerySQL()
+
+	return Expr("("+scope.SQL+")", scope.SQLVars...)
+}
+
 // Where return a new relation, filter records with given conditions, accepts `map`, `struct` or `string` as conditions, refer http://jinzhu.github.io/gorm/crud.html#query
 func (s *DB) Where(query interface{}, args ...interface{}) *DB {
 	return s.clone().search.Where(query, args...).db
@@ -218,7 +227,7 @@ func (s *DB) Group(query string) *DB {
 }
 
 // Having specify HAVING conditions for GROUP BY
-func (s *DB) Having(query string, values ...interface{}) *DB {
+func (s *DB) Having(query interface{}, values ...interface{}) *DB {
 	return s.clone().search.Having(query, values...).db
 }
 

main_test.go

@@ -607,9 +607,54 @@ func TestHaving(t *testing.T) {
 	}
 }
 
+func TestQueryBuilderSubselectInWhere(t *testing.T) {
+	user := User{Name: "ruser1", Email: "root@user1.com", Age: 32}
+	DB.Save(&user)
+	user = User{Name: "ruser2", Email: "nobody@user2.com", Age: 16}
+	DB.Save(&user)
+	user = User{Name: "ruser3", Email: "root@user3.com", Age: 64}
+	DB.Save(&user)
+	user = User{Name: "ruser4", Email: "somebody@user3.com", Age: 128}
+	DB.Save(&user)
+
+	var users []User
+	DB.Select("*").Where("name IN (?)", DB.
+		Select("name").Table("users").Where("email LIKE ?", "root@%").SubqueryExpr()).Find(&users)
+
+	if len(users) != 2 {
+		t.Errorf("Two users should be found, instead found %d", len(users))
+	}
+
+	DB.Select("*").Where("email LIKE ?", "root%").Where("age >= (?)", DB.
+		Select("AVG(age)").Table("users").SubqueryExpr()).Find(&users)
+
+	if len(users) != 2 {
+		t.Errorf("Two users should be found, instead found %d", len(users))
+	}
+}
+
+func TestQueryBuilderSubselectInHaving(t *testing.T) {
+	user := User{Name: "ruser1", Email: "root@user1.com", Age: 64}
+	DB.Save(&user)
+	user = User{Name: "ruser2", Email: "root@user2.com", Age: 128}
+	DB.Save(&user)
+	user = User{Name: "ruser3", Email: "root@user1.com", Age: 64}
+	DB.Save(&user)
+	user = User{Name: "ruser4", Email: "root@user2.com", Age: 128}
+	DB.Save(&user)
+
+	var users []User
+	DB.Select("AVG(age) as avgage").Where("email LIKE ?", "root%").Group("email").Having("AVG(age) > (?)", DB.
+		Select("AVG(age)").Where("email LIKE ?", "root%").Table("users").SubqueryExpr()).Find(&users)
+
+	if len(users) != 1 {
+		t.Errorf("One user group should be found, instead found %d", len(users))
+	}
+}
+
 func DialectHasTzSupport() bool {
 	// NB: mssql and FoundationDB do not support time zones.
-	if dialect := os.Getenv("GORM_DIALECT"); dialect == "mssql" || dialect == "foundation" {
+	if dialect := os.Getenv("GORM_DIALECT"); dialect == "foundation" {
 		return false
 	}
 	return true

scope.go

@@ -253,15 +253,25 @@ func (scope *Scope) CallMethod(methodName string) {
 
 // AddToVars add value as sql's vars, used to prevent SQL injection
 func (scope *Scope) AddToVars(value interface{}) string {
+	_, skipBindVar := scope.InstanceGet("skip_bindvar")
+
 	if expr, ok := value.(*expr); ok {
 		exp := expr.expr
 		for _, arg := range expr.args {
+			if skipBindVar {
+				scope.AddToVars(arg)
+			} else {
 				exp = strings.Replace(exp, "?", scope.AddToVars(arg), 1)
 			}
+		}
 		return exp
 	}
 
 	scope.SQLVars = append(scope.SQLVars, value)
+
+	if skipBindVar {
+		return "?"
+	}
 	return scope.Dialect().BindVar(len(scope.SQLVars))
 }
 
@@ -329,12 +339,12 @@ func (scope *Scope) QuotedTableName() (name string) {
 
 // CombinedConditionSql return combined condition sql
 func (scope *Scope) CombinedConditionSql() string {
-	joinSql := scope.joinsSQL()
+	joinSQL := scope.joinsSQL()
-	whereSql := scope.whereSQL()
+	whereSQL := scope.whereSQL()
 	if scope.Search.raw {
-		whereSql = strings.TrimSuffix(strings.TrimPrefix(whereSql, "WHERE ("), ")")
+		whereSQL = strings.TrimSuffix(strings.TrimPrefix(whereSQL, "WHERE ("), ")")
 	}
-	return joinSql + whereSql + scope.groupSQL() +
+	return joinSQL + whereSQL + scope.groupSQL() +
 		scope.havingSQL() + scope.orderSQL() + scope.limitAndOffsetSQL()
 }
 

search.go

@@ -104,8 +104,12 @@ func (s *search) Group(query string) *search {
 	return s
 }
 
-func (s *search) Having(query string, values ...interface{}) *search {
+func (s *search) Having(query interface{}, values ...interface{}) *search {
+	if val, ok := query.(*expr); ok {
+		s.havingConditions = append(s.havingConditions, map[string]interface{}{"query": val.expr, "args": val.args})
+	} else {
 		s.havingConditions = append(s.havingConditions, map[string]interface{}{"query": query, "args": values})
+	}
 	return s
 }