c 结合oracle

c语言是一门比较经典的编程语言，在计算机科学中有着广泛的应用。而Oracle则是国际一流的企业级数据库系统厂商，提供全面的企业级信息化解决方案。c结合Oracle的应用场景也是非常广泛的。

在c语言中使用Oracle数据库，需要使用Oracle提供的OCI接口库来操作数据库。以下是一个简单的c语言程序使用OCI库来连接Oracle数据库的例子：

#include#include#include#include#define USERNAME "your_username" #define PASSWORD "your_password" #define DATABASE "your_database" int main(int argc, char **argv) { OCIEnv *envhp; OCIError *errhp; OCIServer *srvhp; OCISvcCtx *svchp; OCIStmt *stmthp; OCIDefine *defnp; OCIBind *bindp; char query[1024] = "SELECT * FROM mytable WHERE id = :id"; sword status; /* 初始化 OCI 环境 */ status = OCIEnvCreate(&envhp, OCI_DEFAULT, NULL, NULL, NULL, NULL, 0, NULL); if (status != OCI_SUCCESS) { printf("OCIEnvCreate failed\n"); return -1; } /* 初始化 OCI 错误 */ OCIHandleAlloc(envhp, (void**)&errhp, OCI_HTYPE_ERROR, 0, NULL); if (status != OCI_SUCCESS) { printf("OCIHandleAlloc failed\n"); return -1; } /* 初始化 OCI 服务器 */ OCIHandleAlloc(envhp, (void**)&srvhp, OCI_HTYPE_SERVER, 0, NULL); if (status != OCI_SUCCESS) { printf("OCIHandleAlloc failed\n"); return -1; } /* 连接数据库 */ OCIServerAttach(srvhp, errhp, (text*)DATABASE, strlen(DATABASE), OCI_DEFAULT); if (status != OCI_SUCCESS) { printf("OCIServerAttach failed\n"); return -1; } /* 获取会话上下文 */ OCIHandleAlloc(envhp, (void**)&svchp, OCI_HTYPE_SVCCTX, 0, NULL); if (status != OCI_SUCCESS) { printf("OCIHandleAlloc failed\n"); return -1; } /* 设置会话上下文 */ OCIAttrSet(svchp, OCI_HTYPE_SVCCTX, srvhp, 0, OCI_ATTR_SERVER, errhp); if (status != OCI_SUCCESS) { printf("OCIAttrSet failed\n"); return -1; } /* 开始会话 */ OCIHandleAlloc(envhp, (void**)&stmthp, OCI_HTYPE_STMT, 0, NULL); if (status != OCI_SUCCESS) { printf("OCIHandleAlloc failed\n"); return -1; } /* 准备查询语句 */ OCIStmtPrepare(stmthp, errhp, (text*)query, strlen(query), OCI_NTV_SYNTAX, OCI_DEFAULT); if (status != OCI_SUCCESS) { printf("OCIStmtPrepare failed\n"); return -1; } /* 绑定参数 */ OCIBindByName(stmthp, &bindp, errhp, (text*)":id", strlen(":id"), (void*)&id, sizeof(id), SQLT_INT, NULL, NULL, NULL, 0, NULL, OCI_DEFAULT); if (status != OCI_SUCCESS) { printf("OCIBindByName failed\n"); return -1; } /* 定义结果 */ OCIDefineByPos(stmthp, &defnp, errhp, 1, (void*)&id, sizeof(id), SQLT_INT, NULL, NULL, NULL, OCI_DEFAULT); if (status != OCI_SUCCESS) { printf("OCIDefineByPos failed\n"); return -1; } /* 执行查询 */ OCIStmtExecute(svchp, stmthp, errhp, 1, 0, NULL, NULL, OCI_DEFAULT); if (status != OCI_SUCCESS) { printf("OCIStmtExecute failed\n"); return -1; } /* 处理结果 */ /* 关闭会话 */ /* 断开连接 */ /* 释放 OCI 环境 */ return 0; }