How to using query get inventory AvailPhysical qty

void inventOnHandQuery(ItemID       _itemId,InventBatchId    _batchId)
{
    Query                   g_Query;
    QueryBuildDataSource    qbdISum,qbdIDim;
    QueryBuildRange         qbr;
    InventSum               inventSum;
    QueryRun                locQueryRun;
    Qty                     onHandQty;
    Container               dimActiveFields;
    int                     i   =   1;
    InventDim               inventDim;
    ;
    dimActiveFields =   InventDimSearch::activeFields(InventTable::find(_itemId).DimGroupId);
    g_Query = new Query();

    qbdISum = g_Query.addDataSource(tablenum(inventSum));
    qbdISum.addSortField(fieldNum(inventSum,ItemId));
    qbr     =   qbdISum.addRange(fieldnum(inventSum,ItemId));
    qbr.value(_itemId);
    qbdIDim =   qbdISum.addDataSource(tablenum(InventDim));
    qbdIDim.relations(true);
    qbdIDim.addRange(fieldNum(inventDim,InventBatchId)).value(_batchId);
    while(i <= conlen(dimActiveFields))
    {
        qbdIDim.addSortField(conpeek(dimActiveFields,i));
        i++;
    }
    qbdISum.addRange(fieldNum(inventSum,AvailPhysical)).value(SysQuery::valueNot(0));
    qbdISum.addSelectionField(fieldNum(inventSum,AvailPhysical),SelectionField::Sum);
    qbdIDim.orderMode(OrderMode::GroupBy);
    locQueryRun = new QueryRun(g_Query);
    while(locQueryRun.next())
    {
        inventSum   =   locQueryRun.get(tablenum(InventSum));
        inventDim   =   locQueryRun.get(tablenum(InventDim));
        onHandQty   =   inventSum.AvailPhysical;
        if(InventParameters::find().InventLocationId_DNT != inventDim.InventLocationId)
        {
            if(onceFlag)
            {
                onceFlag    =   false;
                this.createInventJournalTable();
            }
            numOfLines++;
            this.createInventJournalTrans(journalTable.JournalId,_itemId,onHandQty,inventDim);
        }
    }

    return ;
}