我想你和我一样,照着终于编译好了qt的oracle驱动QOCI,连接成功!!! 一文编译了QOCI,我目前遇到下面错误:(代码我直接用原文的) QSqlDatabase: QOCI driver not loadedQSqlDatabase: available drivers: QSQLITE QMYSQL QMYSQL3 QODBC QODBC3 QPSQL QPSQL7e
我想你和我一样,照着终于编译好了qt的oracle驱动QOCI,连接成功!!!
一文编译了QOCI,我目前遇到下面错误:(代码我直接用原文的)
QSqlDatabase: QOCI driver not loaded QSqlDatabase: available drivers: QSQLITE QMYSQL QMYSQL3 QODBC QODBC3 QPSQL QPSQL7 error_Oracle: "Driver not loaded Driver not loaded"
解决这个问题就得从原理上说:
thin是纯java实现tcp/ip的c/s通讯;而oci方式,客户端通过native java method调用c library访问服务端,而这个c library就是oci(oracle called interface),因此这个oci总是需要随着oracle客户端安装(从oracle10.1.0开始,单独提供OCI Instant Client,不用再完整的安装client)
很多时候我们都考虑我们编译的$QTDIR/plugins/sqldrivers 下DLL 是否正确加载,而忽略Oracle那边的库是否加载。
那么问题解决方法就是
方法1、在系统Path 就是环境变量中添加 你的Oracle oci.dll库位置 C:\oracle\product\10.2.0\client_1\BIN。如果你正确安装Oracle客户端,就不应该存在这个问题。
方法2、有点土就是用QT自带 loadlibrary 自己加载oci.dll库位置。
我用的方法是1+2,已经测试无问题。
QLibrary *hello_lib = NULL; //写清楚库的路径,如果放在当前工程的目录下,路径为./Oracle.so hello_lib = new QLibrary("C:\\oracle\\product\\10.2.0\\client_1\\BIN\\oci.dll"); //加载动态库 hello_lib->load(); if (!hello_lib->isLoaded()) { printf("load Oracle failed!\n"); return ; }
但要注意不管方法1或者方法2,Oracle 客户端是必须要装的,另外我不知道QT各版本编译出来的库是否通用,自己编译比较好。
WIN7 我还遇到一个问题:
QOCIDriver: unable to create environment error_Oracle: " Unable to logon"
这个你用PL/SQL应该遇到过
解决方法:
1、右键用 管理员身份账户 运行
2、程序路径不能有(),类似"C:\Program Files (x86)" 这样的路径无法登陆。我只知道10 是不行,不知道12改了没有。

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