数据库操作封装 功能：获得结果集的行数，数据库增删改操作，数据库查询，获得结果内容，获得单例模式类指针-Operation of the database package features: the number of rows in the result set, database growth, delete, change operations, database queries, results obtained content, access to the singleton cl

my singleton patten interface

自己写得单件模式，重要基本模式之一，供大家参考。-Write their own one-piece model, it is important to one of the basic pattern for reference.

自己写得单件模式，重要基本模式之一，供大家参考。-Write their own one-piece model, it is important to one of the basic pattern for reference.