应用服务器未安装oracle，安装PLSQL的方法

1.下载一个instantclient

http://www.oracle.com/technetwork/cn/database/features/instant-client/index-092699-zhs.html

2.创建一个目录存放instantclient 

例D:\instantclient_12_1

3. 在instantclient文件夹下创建两个文件(sqlnet.ora和tnsnames.ora)

sqlnet.ora

SQLNET.AUTHENTICATION_SERVICES= (NTS)NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)

tnsnames.ora

ORCL=  (DESCRIPTION =    (ADDRESS_LIST =      (ADDRESS = (PROTOCOL = TCP)(HOST = IP)(PORT = 1521))    )    (CONNECT_DATA =      (SERVICE_NAME = orcl)    )  )

4.配置系统变量

变量名：TNS_ADMIN

  变量值：D:\nstantclient_12_1（之前创建的目录）

5.打开PL/SQL，Tools-->Preferences

6.重启PLSQL