Tuesday, July 6, 2010

Conditional Joins in x++

In this post, we will try to learn how we can apply conditional joins in x++ to cater the complex scenarios in the development of Microsoft Dynamics AX.

Conditional joins in Dynamics AX (x++)
Here is the code to apply joins conditionally in Microsoft Dynamics AX.
query = new Query();
dsInventTable = query.addDataSource(tableNum(InventTable), "InventTable");
dsInventItemBarCode = dsInventTable.addDataSource(tableNum(InventItemBarCode), "InventItemBarCode");

// Add our two ranges
queryBuildRange1 = dsInventTable.addRange(fieldNum(InventTable, DataAreaId));
queryBuildRange2 = dsInventItemBarCode.addRange(fieldNum(InventItemBarCode, DataAreaId));

No we can play with our query  
Find all records where either the ItemType is Service, or the ItemType is Item and a barcode exists. The join criteria is only applied in the second half of the expression, so all Service items will appear irrespective of whether they have a bar code. Again, this is not possible to achieve using the standard query ranges.

queryBuildRange2.value(strFmt('((%1.%2 == %3) || ((%1.%2 == %4) && (%1.%5 == %6)))',
query.dataSourceTable(tableNum(InventTable)).name(), // InventTable %1
fieldStr(InventTable, ItemType), // ItemType %2
any2int(ItemType::Service), // %3
any2int(ItemType::Item), // %4
fieldStr(InventTable, ItemId), // ItemId %5
fieldStr(InventItemBarCode, ItemId))); // %6