从 sql 2008 表中获取向量

Question

I have a table called test with 6 columns and 6 rows in SQL server 2008:

1att  2att  3att  4att  5att  6att 
----------------------------------     
467   116   480   477   491  697  
NULL  219   481   113   488  466  
NULL  NULL  477   466   455  480  
NULL  NULL  NULL  527   483  629  
NULL  NULL  NULL  NULL  483  483  
NULL  NULL  NULL  NULL  NULL 697  

I would like to have a vector with all values, but with column order.

so my vector would look like

[ 
    467  116   480   477   491  697    //row 1
    116  219   481   113   488  466    //row 2
    480  481   477   466   455  480    //row 3
    477  113   466   527   483  629    //row 4
    491  488   455   483   483  483    //row 5
    697  466   480   629   483  697    //row 6

 ]

To do this I am using Visual Studio 2008,with c++, nd for connecting using ADO.

// svd-conn.cpp: archivo de proyecto principal.
#include "stdafx.h"
#include <iostream>
#include <string>
#include <windows.h>
#define MSADO15_PATH "c:\program files\common files\system\ado\msado15.dll"
#ifdef _MSC_VER
    #import MSADO15_PATH rename ("EOF","adoEOF") no_namespace
#else
#define V_INT(X)         V_UNION(X, intVal)
#define V_UINT(X)        V_UNION(X, uintVal)
#include "msado15.tlh"
#endif

#include <comutil.h>

struct InitOle{
     InitOle()  { ::CoInitialize(NULL); }
    ~InitOle() { ::CoUninitialize();   }
} InitOle_tag;

//------------------ utility fns to simplify access to recordset fields
_bstr_t RsItem( _RecordsetPtr p, BSTR fldName ){
    // by field name
    return( p->Fields->Item[_variant_t(fldName)]->Value );
}
_bstr_t RsItem( _RecordsetPtr p, long nIdx ){
    // by field # (0 is first)
    return( p->Fields->Item[_variant_t(nIdx)]->Value );
}
//-------------------------------- The Program ----------------
int main(){
    _RecordsetPtr spRs;
    HRESULT hr;
    _bstr_t sConn= "driver={sql server};SERVER=VIRTUALPC;Database=test;UID=sa; PWD=;";
    _bstr_t sSQL= "SELECT * FROM dbo.test ;";

    try{
        hr= spRs.CreateInstance( __uuidof(Recordset) );
        if FAILED(hr)
            printf("CreateInstance failed\n");
        else
            printf("CreateInstance SUCCESS\n");

        hr= spRs->Open( sSQL, sConn, adOpenForwardOnly, adLockReadOnly, adCmdText );
        if FAILED(hr) 
            printf("Open failed\n");
        else
            printf("Open SUCCESS\n");

        printf("spRs->adoEOF %s\n",spRs->adoEOF);
        while( !(spRs->adoEOF) ) {
            printf("%s\t%s\n",(char*) RsItem( spRs, 0L ),(char*) RsItem( spRs, 1L ),(char*) RsItem( spRs, 2L ) );
            spRs->MoveNext();
        }

        spRs->Close();

    } catch( _com_error &e) {
        printf("Error:%s\n",(char*)e.Description());
    }
    return 0;
}

with that code, inside the while loop I can get the values, but How could I insert them the right way in the vector?

So How could I incorporate vector class:

vector <double> v;
And have the wished vector??

I know that to insert to vector I do this

v.push_back(467); ....

but how to do it programatically, in fact the NULLS are the real problem...

Answer 1

From the question: in fact the NULLS are the real problem ...
A relatively simple problem indeed. By keeping track of the row and column, and since the vector is filled-in in row order, the values of the cell below the diagonal can be obtained from their transpose location, ie in value of data readily in the vector.
Maybe something like the following:

#define COLS_PER_ROW 6
int rowNum = 0;
vector <double> v(COLS_PER_ROW * COLS_PER_ROW, 0);     
while( !(spRs->adoEOF) ) {
    for (colNum = 0; colNum < COLS_PER_ROW; colNum++)
    {
       double dVal;
       bstr_t sVal = RsItem(spRs, colNum);
       if (sVal) // this test is equivalent to if (colNum >= rowNum)
       {
           dval = strtod(sVal, NULL);
       }
       else
           dVal = v[colNum * COLS_PER_ROW + rowNum];  // not an error as we want to read the transpose loc for the cell.
    }
    rowNum++;
    spRs->MoveNext();
}

A small note on the test for a null value
if (sVal) tests if the database-supplied value was null.
a better test may be
if (colNum >= rowNum) ie assuming that the null values are found in the lower triangle, and in agreement with our getting the value in the "mirror"/"transpose" location in the upper triangle.