oralob.cpp

在动态库中实现异步导出大数据量的oracle数据

#include "stdafx.h"

#define __OCICPP_INTERNAL_USE_
#include "OraLob.h"

/*!
  \class OCICPP::OraLob
  \brief Client-side representation of an Oracle Large Object cell
 */

OCICPP::OraLob::OraLob(OCIEnv *envhp,OCIError *errhp,OCIParam *param,OCISvcCtx *svc,ub2 lob_type,int rows): 
				OraType(envhp,errhp,param,lob_type,rows),lob(0),svchp(svc),type(lob_type)
{
	ReqType=lob_type;
	size=0;
	lob=(OCILobLocator **)calloc(nRows,sizeof(OCILobLocator *));
	for(int i=0;i<nRows;i++) {
		if(lob_type==SQLT_FILE) {
			if(OCIDescriptorAlloc((void *)envhp,(void **)&lob[i],OCI_DTYPE_FILE,0,0)!=OCI_SUCCESS) {
				throw OraError("OCICPPLIB: Cannot make new LOB: Handle Allocation failed",OCICPPERROR);
			}
		} else { 
			if(OCIDescriptorAlloc((void *)envhp,(void **)&lob[i],OCI_DTYPE_LOB,0,0)!=OCI_SUCCESS) {
				throw OraError("OCICPPLIB: Cannot make new LOB: Handle Allocation failed",OCICPPERROR);
			}
		}
	}
}

OCICPP::OraLob::~OraLob() {
	for(int i=0;i<nRows;i++) {
		OCIDescriptorFree(lob[i],OCI_DTYPE_LOB);
	}
	free(lob);
	OCIHandleFree(definehp,OCI_HTYPE_DEFINE);
}

void OCICPP::OraLob::define(OCIStmt *stmt,int col) {
	 CHECKERR(err, OCIDefineByPos(stmt,&definehp, err, col+1, lob, -1,ReqType,
	                                (dvoid *) null, 0, (ub2 *)0, OCI_DEFAULT)); 
}

void OCICPP::OraLob::getCLOB(Lob &ulob,int row) {
	ulob.init(svchp,lob[row],err,CLOB,CACHE_OFF);
}

void OCICPP::OraLob::getBLOB(Lob &ulob,int row) {
	ulob.init(svchp,lob[row],err,BLOB,CACHE_OFF);
}

void OCICPP::OraLob::getStr(std::string &str,int row) {
	Lob ulob;
	ulob.init(svchp,lob[row],err,BLOB,CACHE_OFF);
	char buf[512];
	unsigned actread;
	str="";
	while(actread=ulob.read(buf,255)) {
		buf[actread]='\0';
		str+=buf;
	}
}