c oracle 结果集

在大多数应用中，C语言使用Oracle数据库时，需要进行结果集处理。结果集指的是查询结果中的所有行和列。结果集中的行可以存储在内存中，也可以随着需要动态获取。结果集中的列包含数据类型和名称等信息。C语言提供了一些库和API，可以很方便地处理这些结果集。

通过Oracle数据库可以非常容易地处理大量数据，并使用C语言对结果集进行操作。举个例子，我们可以使用以下代码来执行查询操作：

#include #include #include main() { OCIEnv *envhp; OCIServer *srvhp; OCIError *errhp; OCISession *usrhp; OCISvcCtx *svchp; OCIStmt *stmthp; OCIDefine *defnp; sword status; ub4 x,y; OCIInitialize((ub4) OCI_OBJECT, (dvoid *)0, (dvoid * (*)(size_t)) 0, (dvoid * (*)(dvoid *, size_t)) 0, (void (*)(dvoid *)) 0 ); OCIEnvInit( &envhp, OCI_DEFAULT, (size_t) 0, (dvoid **) 0 ); OCIHandleAlloc( (dvoid *) envhp,(dvoid **) &errhp,(ub4) OCI_HTYPE_ERROR,(size_t) 0,(dvoid **) 0); OCIHandleAlloc( (dvoid *) envhp,(dvoid **) &srvhp,(ub4) OCI_HTYPE_SERVER,(size_t) 0,(dvoid **) 0); OCIHandleAlloc( (dvoid *) envhp,(dvoid **) &usrhp,(ub4) OCI_HTYPE_SESSION,(size_t) 0, (dvoid **) 0); OCIHandleAlloc( (dvoid *) envhp,(dvoid **) &svchp,(ub4) OCI_HTYPE_SVCCTX,(size_t) 0, (dvoid **) 0); OCILogon2(envhp, errhp, &svchp, "username", strlen("username"), "password", strlen("password"), "database", strlen("database"), OCI_DEFAULT); OCIStmtPrepare(stmthp, errhp, (text*) "select * from table_name", strlen("select * from table_name"), OCI_DEFAULT); status = OCIStmtExecute(svchp, stmthp, errhp, (ub4) 0, (ub4) 0, (CONST OCISnapshot *) NULL, (OCISnapshot *) NULL, OCI_DEFAULT); if (status != OCI_SUCCESS){OCIHandleFree((dvoid *) errhp, OCI_HTYPE_ERROR);OCIHandleFree((dvoid *) svchp, OCI_HTYPE_SVCCTX);} for (x = 1; x