Support Having w/o Group

clause/group_by.go

@@ -39,4 +39,10 @@ func (groupBy GroupBy) MergeClause(clause *Clause) {
 		groupBy.Having = append(copiedHaving, groupBy.Having...)
 	}
 	clause.Expression = groupBy
+
+	if len(groupBy.Columns) == 0 {
+		clause.Name = ""
+	} else {
+		clause.Name = groupBy.Name()
+	}
 }

tests/group_by_test.go

@@ -96,4 +96,14 @@ func TestGroupBy(t *testing.T) {
 	if name != "groupby" || active != true || total != 40 {
 		t.Errorf("group by two columns, name %v, age %v, active: %v", name, total, active)
 	}
+
+	if DB.Dialector.Name() == "mysql" {
+		if err := DB.Model(&User{}).Select("name, age as total").Where("name LIKE ?", "groupby%").Having("total > ?", 300).Scan(&result).Error; err != nil {
+			t.Errorf("no error should happen, but got %v", err)
+		}
+
+		if result.Name != "groupby1" || result.Total != 330 {
+			t.Errorf("name should be groupby, total should be 660, but got %+v", result)
+		}
+	}
 }