首先下载instantclient 可以到oracle官网下载，要注册账号，一定要下对应版本的，要不然不成功，
10g,11g版的,我已经传上来了，免费下载:正在上传中，稍等
配置文件tnsnames.ora 这个一个地方一般都放(network/admin)，只有在pl/sql —–>tools–>proferences…——>connection—-> oracle home(empty is autodetect) 写上tnsnames.ora的路径（相关路径换成你自已的）
orcl2 =
(description =
(address_list =
(address = (protocol = tcp)(host = 172.16.100.183)(port = 1521))
)
(connect_data =
(service_name = orcl)
)
)
oraclr_connection_data =
(description =
(address_list =
(address = (protocol = ipc)(key = extproc1521))
)
(connect_data =
(sid = clrextproc)
(presentation = ro)
)
)
设置环境变量（目录换成你自已的）
tns_admin=d:\soft\oarcleclient\instantclient_11_2
nls_lang=simplified chinese_china.zhs16gbk
path=d:\soft\oarcleclient\instantclient_11_2