数据库读clob解决办法

int CEntityBase::readClob(OCIClobLocator *p_clob, char* buff){        struct sqlca sqlca;    EXEC SQL CONTEXT USE:m_pWorkThread->m_pvSqlCtx;        EXEC SQL BEGIN DECLARE SECTION;                OCIClobLocator *clob;                varchar *lvr;                int amt;                int bufsize;        EXEC SQL END DECLARE SECTION;        #if 0    if(sqlca.sqlcode != 0)        {                return sqlca.sqlcode;        }        #endif    bufsize = 2048;        clob = p_clob;        char* tmp = new char[2 + bufsize];        memset(tmp, 0, 2+bufsize);        lvr = (varchar *)tmp;        lvr->len = bufsize;        int len = 0;        amt = 0;        EXEC SQL WHENEVER NOT FOUND DO break;        while (TRUE)        {                memset(lvr,0,2+bufsize);                EXEC SQL LOB READ :amt FROM :clob INTO :lvr WITH LENGTH :bufsize;                strcat(buff, (char *)lvr->arr);//        memcpy(buff + len, lvr->arr, lvr->len);//        len += lvr->len;        }        EXEC SQL WHENEVER NOT FOUND CONTINUE;        strcat(buff, (char *)lvr->arr);//    memcpy(buff + len, lvr->arr, lvr->len);//    len += lvr->len;//    buff[len] = 0;        delete[] tmp;    return 0;}