1、下载好Instant Client,解压好，如图：
2、配置InstantClient:在instantclient解压目录下分别新建如下两个文件tnsnames.ora/listener.ora。编辑listener.ora内容：LISTENER1 = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521)) )编辑tnsnames.ora内容：ORCL = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = orcl) ) )EXTPROC_CONNECTION_DATA = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1)) ) (CONNECT_DATA = (SID = PLSExtProc) (PRESENTATION = RO) ) )如下图：
3、配置instantclient的环境变量：在电脑的系统环境变量下，增加如下环境变量1、NLS_LANG=AMERICAN_AMERICA.ZHS16GBK2、Path添加：G:\Program Files\instantclient_11_23、TNS_ADMIN=G:\Program Files\instantclient_11_2
4、PL/Sql配置InstantClient路径:进入PL/Sql点击工具->首选项 出现如图配置界面这里在左侧菜单项找到到连接，点击后会在右侧出现如图配置界面，在红色箭头标注位置替换InstantClient的解压路径oracle主目录名：D:\Program Files\instantclient_11_2OCI库：D:\Program Files\instantclient_11_2\oci.dll如图
5、重启PL/Sql Developer然后发现数据库出现在了plsql的登录界面，此时Oracle可以用plsql正常使用了。如图：
