验证时，只要不报错就认为连接有效

[shlijun]

Oracle JDBC连接初始化时无法指定Schema（与登录用户不同），通过验证连接进行状态验证的同时切换Schema（alter session set current_schema = xxxx），该语句没有返回值，rs.next()是false，导致使用异常

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