How to: Use the Query Class to Read From a Valid Time State Table

项目
05/18/2015

Applies To: Microsoft Dynamics AX 2012 R3, Microsoft Dynamics AX 2012 R2, Microsoft Dynamics AX 2012 Feature Pack, Microsoft Dynamics AX 2012

You can use the Query class to read rows from a valid time state table. Methods such as validTimeStateDateRange enable this functionality.

For more information about valid time state tables, see Valid Time State Tables and Date Effective Data.

Valid Time State Methods on the Query Class

The following methods on the Query class enable you to read from a valid time state table. These methods give you the same control that the validTimeState keyword gives to you in an X++ select statement:

validTimeStateAsOfDate
validTimeStateAsOfDateTime
validTimeStateDateRange
validTimeStateDateTimeRange

Code Example

The following code example uses the Query class to read all of the rows from a valid time state table. Pay attention to the validTimeStateDateRange method.

If you want to run the following code example, you must first run the code examples in the topic Effects of Valid Time State Tables on Read and Write Operations.

    static void QueryVtsJob60(Args _args)  // X++ job, under AOT > Jobs.
    {
        TabEmplProjVts xEP;
        Query qry;
        QueryRun qRun;
        QueryBuildDataSource qBDSource;
        str sDisplay;
        int iTableNumEP = tableNum(TabEmplProjVts);
        date dateMinimum = 1\1\1900,
            dateMaximum = 31\12\2154;
        
        qry = new Query();
        qry.validTimeStateDateRange(dateMinimum, dateMaximum);
        qBDSource = qry.addDataSource(iTableNumEP);
        qBDSource.addOrderByField(fieldNum(TabEmplProjVts, EmplID));
        qBDSource.addOrderByField(fieldNum(TabEmplProjVts, ProjID));
        qBDSource.addOrderByField(fieldNum(TabEmplProjVts, ValidFrom));
        qRun = new QueryRun(qry);
    
        while (qRun.next())
        {
            xEP = qRun.get(iTableNumEP);
            sDisplay = xEP.EmplID
                + " , " + xEP.ProjID
                // Or use the enums DateFormat, DateDay, DateMonth
                // and DateYear for parameter values into date2str.
                + " .  " + date2str(xEP.ValidFrom, 321, 2,3,2,3,4)
                + " -- " + date2str(xEP.ValidTo, 321, 2,3,2,3,4)
                + " .  " + xEP.EPPrimaryKey;
            Global::info(sDisplay);
        }
    }

Infolog Display

In the following output, you can see that the retrieved rows include a variety of date ranges, even for the same pairs of employee plus project. The varied date ranges displayed in the output indicate that the validTimeStateDateRange method did override the default of the current system date. For instance, no single date can retrieve the rows that have key61 and key62.

Message (02:31:03 pm)
em21 , pr44 . 2000-01-01 -- 2003-12-31 . key61
em21 , pr44 . 2004-01-01 -- 2039-12-31 . key62
em22 , pr44 . 2001-01-01 -- 2005-12-31 . key63
em22 , pr44 . 2009-01-01 -- 2038-12-31 . key64
em22 , pr45 . 1910-02-13 -- 1924-03-14 . key65
em22 , pr45 . 1936-05-16 -- 1948-06-17 . key66
em22 , pr45 . 2111-07-18 -- 2119-08-19 . key67

通过

How to: Use the Query Class to Read From a Valid Time State Table

Valid Time State Methods on the Query Class

Code Example

Infolog Display

See also

其他资源