nstantclient-basic-nt-12.1.0.1.0\instantclient_12_1下面新建NETWORK文件夹，NETWORK下新建ADMIN文件夹，ADMIN下新建tnsnames.ora文件，内容

ORCL=
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = ORCL)
    )
  )