本机oracle测试库sys密码忘了，查了查解决方法，结果又碰到问题，又解决：
连接时候：connect /as sysdba
ERROR:
ORA-12560:TNS:协议适配器错误
解决方法：
1.services.msc服务中启动oracle9iTNSListener服务。
2.启动oracleServiceXXX，XXX为数据库SID
3.regedit修改HKEY_LOCAL_MACHINE/SOFTEWARE/ORACLE将环境变量oracle_sid设为XXX，XXX为数据库SID
继续sys密码修改：
oracle 提供两种验证方式，一种是OS验证，一种是密码文件验证方式，我采用第一种方式：
sqlplus /nolog
connect / as sysdba
alter user sys identified by XXX; xxx新密码
alter user system identified by XXX; xxx新密码
设定完后重启登录
显示当前数据库：
show parameter db_name
show parameter service
修改密码后登录：
sqlplus sys/xxx as sysdba
登录成功
sqlplus sys/xxx@orcl as sysdba报错：
TNS:连接超时
修改tnsnames.ora
ORCL =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
sqlplus sys/xxx@orcl as sysdba报错：
ORA-12514: TNS:监听程序当前无法识别连接描述符中请求的服务
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = D:/oracle/product/10.2.0/db_1)
(PROGRAM = extproc)
)
(SID_DESC =
(GLOBAL_DBNAME = ORCL)
(ORACLE_HOME = D:/oracle/product/10.2.0/db_1)
(SID_NAME = ORCL)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
)
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))
)
)
以上粗体部件为增加的内容，修改后重启监听服务后即可。
创建用户：
create user username identified by pwd;
grant connect,resource,dba to username;角色权限