connectstring="user id=你的用户名称;data source=BXHAPL4（你在tnsnames.ora文件中的数据库名称，看下面的文件）;password=你的数据库口令")
当然你必须有tnsnames.ora文件，类似于
# TNSNAMES.ORA Network Configuration File: C:\oracle\ora92\NETWORK\ADMIN\tnsnames.ora
# Generated by Oracle configuration tools.
BXHAPL4 =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = CNABB-ATPM-WSK)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = BXHAPL4.ABB.COM)
(SID = BXHAPL4)
)
)
MASTER =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = cnabb-atpm-wsk)(PORT = 1521))
)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = master)
)
)
INST1_HTTP =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = cnabb-atpm-wsk)(PORT = 1521))
)
(CONNECT_DATA =
(SERVER = SHARED)
(SERVICE_NAME = MODOSE)
(PRESENTATION = http://HRService)
)
)
EXTPROC_CONNECTION_DATA =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
)
(CONNECT_DATA =
(SID = PLSExtProc)
(PRESENTATION = RO)
)
)
这样你的连接字符串就知道从这个文件中找到自己需要连接数据库的IP地址，端口以及其他的连接参数。
