Проводки переноса в AX2012

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В методе TransferInventTransOrigin таблицы InventTrans есть код, который вычисяет номер лота связанной проводки переноса (по отношению к текущей проводке):

  // don't combine the statements below as that most likely results in wide index scans instead of narrow index seeks.
    if (this.Qty <= 0)
    {   // This is most likely the standard issue of a transfer so try that first.
        select firstonly inventTransOrigin
            exists join inventTransOriginTransfer
            where   inventTransOriginTransfer.IssueInventTransOrigin    == this.InventTransOrigin
                 && inventTransOriginTransfer.ReceiptInventTransOrigin  == inventTransOrigin.RecId;

        if (!inventTransOrigin.RecId)
        { // This wasn't the issue - try the receipt
            select firstonly inventTransOrigin
                exists join inventTransOriginTransfer
                where   inventTransOriginTransfer.IssueInventTransOrigin    == inventTransOrigin.RecId
                     && inventTransOriginTransfer.ReceiptInventTransOrigin  == this.InventTransOrigin;
        }
    }
    else
    {   // This is most likely the standard receipt of a transfer so try that first.
        select firstonly inventTransOrigin
            exists join inventTransOriginTransfer
            where   inventTransOriginTransfer.IssueInventTransOrigin    == inventTransOrigin.RecId
                 && inventTransOriginTransfer.ReceiptInventTransOrigin  == this.InventTransOrigin;

        if (!inventTransOrigin.RecId)
        { // This wasn't the receipt - try the issue
            select firstonly inventTransOrigin
                exists join inventTransOriginTransfer
                where   inventTransOriginTransfer.IssueInventTransOrigin    == this.InventTransOrigin
                     && inventTransOriginTransfer.ReceiptInventTransOrigin  == inventTransOrigin.RecId;
        }
    }

У меня вопрос, как могут быть проводки расхода с положительным знаком или проводки прихода с отрицательным? Дело в том, что для OLAP мне необходимо реализовать связь проводок переноса с помощь view и не хотелось бы ненужных усложнений.