1、在oracle网站下载Instant Clinet Package的软件包（basic），解压，目录随意，这里以c:\oracleclient为例
2、在c:\oracleclient里创建network/admin目录，增加tnsnames.ora文件，内容如下
ORCL = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = xx.xx.xx.xx)(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) ) )?
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3、安装PLSQl developer 客户端
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4、工具---》首选项---》链接
???? 设置oracle home（oracle主目录）和OCI 库位置
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5、重启qlsql developer
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问题：报错说找不到msvcr71.dll
解决：从http://www.dll-files.com/dllindex/dll-files.shtml?msvcr71 下载该dll，放入c:\oracleclient里