C oracle api
C oracle api是为了简化与Oracle数据库的交互而设计的一组API接口。它可以帮助开发人员简化数据管理、查询和存储等重要工作。C oracle api还可以允许开发人员通过外部C程序来直接与Oracle数据库进行通信。
为了更好地了解C oracle api的使用，以下是一些使用C oracle api时常用的代码示例：
// 连接到Oracle数据库
OCIDefine handle;
OCIStmt stmt;
//...
// 创建数据库连接指针
OCIEnvCreate(&env, OCI_DEFAULT, (dvoid *) 0,
(dvoid * (*)(void *, size_t)) 0,
(dvoid * (*)(void *, void *, size_t)) 0,
(void (*)(void *, void *)) 0, 0, (dvoid **)0);
OCIHandleAlloc((dvoid *)env, (dvoid **)&err, OCI_HTYPE_ERROR, (size_t)0, (dvoid **)0);
OCIHandleAlloc((dvoid *)env, (dvoid **)&srv, OCI_HTYPE_SERVER, (size_t)0, (dvoid **)0);
OCIHandleAlloc((dvoid *)env, (dvoid **)&svc, OCI_HTYPE_SVCCTX, (size_t)0, (dvoid **)0);
OCIHandleAlloc((dvoid *)env, (dvoid **)&authp, OCI_HTYPE_SESSION, (size_t)0, (dvoid **)0);
OCIServerAttach(srv, err, (const OraText *)"//127.0.0.1:1521/orcl", strlen("//127.0.0.1:1521/orcl"), OCI_DEFAULT);
OCIAttrSet((dvoid *)svc, OCI_HTYPE_SVCCTX, (dvoid *)srv, (ub4)0, OCI_ATTR_SERVER, err);
OCIAttrSet((dvoid *)authp, OCI_HTYPE_SESSION, (dvoid *)"test", strlen("test"), OCI_ATTR_USERNAME, err);
OCIAttrSet((dvoid *)authp, OCI_HTYPE_SESSION, (dvoid *)"123456", strlen("123456"), OCI_ATTR_PASSWORD, err);
OCISessionBegin(svc, err, authp, OCI_CRED_RDBMS, OCI_DEFAULT);
OCIAttrSet((dvoid *)svc, OCI_HTYPE_SVCCTX, (dvoid *)authp, (ub4)0, OCI_ATTR_SESSION, err);
// 查询数据
char str_sql[256]="select test1, test2 from userinfo";
OCIResult* p_result;
OCIStmt* p_stmt;
OCIDefine* p_define=NULL;
OCIBind p_bind2[2];
sb4 s_res=0;
OCIHandleAlloc( (dvoid *)env, (dvoid **)&stmt, OCI_HTYPE_STMT, (size_t)0, (dvoid **)0 );
if(OCIStmtPrepare(stmt, err, (text*)str_sql, strlen(str_sql), OCI_NTV_SYNTAX, OCI_DEFAULT)!=OCI_SUCCESS)
{
printf("SQL Error: Statement couldn't be prepared\n");
}
OCIParamGet(stmt, OCI_HTYPE_STMT, err, (void **)&p_result, 1);
OCIAttrGet(p_result, OCI_DTYPE_PARAM, (void **)&p_define[0], (ub4*)0, OCI_ATTR_NAME, err);
OCIAttrGet(p_result, OCI_DTYPE_PARAM, (void **)&p_define[1], (ub4*)0, OCI_ATTR_NAME, err);
OCIDefineByPos(stmt, &p_define[0], err, 1, NULL, 0, SQLT_STR, NULL, NULL, NULL, OCI_DEFAULT);
OCIDefineByPos(stmt, &p_define[1], err, 2, NULL, 0, SQLT_NUM, NULL, NULL, NULL, OCI_DEFAULT);
if(OCIDefineByPos(stmt, &p_define[0], err, 1, NULL, 0, SQLT_STR, NULL, NULL, NULL, OCI_DEFAULT)!=OCI_SUCCESS)
{
OCIHandleFree(stmt, OCI_HTYPE_STMT);
printf("SQL Error: Binding statements failed\n");
}
if(OCIDefineByPos(stmt, &p_define[1], err, 2, NULL, 0, SQLT_NUM, NULL, NULL, NULL, OCI_DEFAULT)!=OCI_SUCCESS)
{
OCIHandleFree(stmt, OCI_HTYPE_STMT);
printf("SQL Error: Binding statements failed\n");
}
/* Execute the SQL statement */
if(OCIStmtExecute(svc, stmt, err, (ub4)1, (ub4)0, (CONST OCISnapshot*)NULL, (OCISnapshot*)NULL, OCI_COMMIT_ON_SUCCESS)!=OCI_SUCCESS)
{
OCIHandleFree(stmt, OCI_HTYPE_STMT);
printf("SQL Error: Statement execution failed\n");
}
/* Fetch the rows */
while((s_res = OCIStmtFetch(stmt, err, 1, OCI_FETCH_NEXT, OCI_DEFAULT))!=OCI_NO_DATA)
{
printf("Name: %s, Test result: %d\n", sql_names, sql_tests);
}
// 关闭数据库连接
OCILogoff(svc, err);
