第一次用的时候一点问题都没有，后来把oracleservice和listening两个服务停掉之后再用就出现：
ORA-12505, TNS:listener does not currently know of SID given in connect descriptor
解决办法是修改D:\app\Administrator\product\11.1.0\db_1\NETWORK\ADMIN下的listener.ora
改成：
# listener.ora Network Configuration File: d:\app\Administrator\product\11.1.0\db_1\network\admin\listener.ora
# Generated by Oracle configuration tools.
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = D:\app\Administrator\product\11.1.0\db_1)
(PROGRAM = extproc)
)
(SID_DESC =
(GLOBAL_DBNAME = orcl)
(ORACLE_HOME = D:\app\Administrator\product\11.1.0\db_1)
(SID_NAME = orcl)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
)
)
重启oracleservice和listening两个服务即可。