fix: 查询nil字符串序列非空字符串

features/sys_user/service/repo_sys_user.go

@@ -572,7 +572,11 @@ func (r *RepoSysUser) CheckUniqueUser(sysUser sysUserModel.SysUser) string {
 		log.Errorf("query err %v", err)
 	}
 	if len(results) > 0 {
-		return fmt.Sprintf("%v", results[0]["str"])
+		v, ok := results[0]["str"].(string)
+		if ok {
+			return v
+		}
+		return ""
 	}
 	return ""
 }