All docs
V21.1
21.2 (EAP/Beta)
21.1
20.2
The page you are viewing does not exist in version 20.2. This link will take you to the root page.
20.1
The page you are viewing does not exist in version 20.1. This link will take you to the root page.
19.2
The page you are viewing does not exist in version 19.2. This link will take you to the root page.
19.1
The page you are viewing does not exist in version 19.1. This link will take you to the root page.
18.2
The page you are viewing does not exist in version 18.2. This link will take you to the root page.
18.1
The page you are viewing does not exist in version 18.1. This link will take you to the root page.
17.2
The page you are viewing does not exist in version 17.2. This link will take you to the root page.

TransformationNodeBuilder.Build() Method

Builds a transformation node.

Namespace: DevExpress.DataAccess.DataFederation

Assembly: DevExpress.DataAccess.v21.1.dll

Declaration

public TransformationNode Build()

Returns

Type Description
TransformationNode

A transformation node.

Example

The following example demonstrates how to unfold and flatten the Products array of two data sources and unite data from these sources.

Show JSON Data (Products1.json)
[
    {
        "CategoryID": 1,
        "Products":
        [
            {
                "ProductName": "Chai",
                "UnitPrice": 18
            },
            {
                "ProductName": "Chang",
                "UnitPrice": 19
            }
        ]
    },
    {
        "CategoryID": 2,
        "Products":
        [
            {
                "ProductName": "Ikura",
                "UnitPrice": 31
            },
            {
                "ProductName": "Konbu",
                "UnitPrice": 6
            }
        ]
    }
]
Show JSON Data (Products2.json)
[
    {
        "CategoryID": 1,
        "Products":
        [
            {
                "ProductName": "Chai",
                "UnitPrice": 18
            },
            {
                "ProductName": "Chang",
                "UnitPrice": 19
            }
        ]
    },
    {
        "CategoryID": 2,
        "Products":
        [
            {
                "ProductName": "Ikura",
                "UnitPrice": 31
            },
            {
                "ProductName": "Konbu",
                "UnitPrice": 6
            }
        ]
    }
]
using DevExpress.DataAccess.DataFederation;
using DevExpress.DataAccess.Json;
// ...
var source1 = new Source("Products1", jsonDataSource1);
var source2 = new Source("Products2", jsonDataSource2);

var query1 = source1
    .Transform()
    .TransformColumn("Products")
    .Build();

var query2 = source2
    .Transform()
    .TransformColumn("Products")
    .Build();

var query = query1
    .Union(query2)
    .Build("ProductsUnited");

var federation = new FederationDataSource() {
    Queries = { query }
};

The following schema is the result of the transformation:

"CategoryID": int
"Products_ProductName": string
"Products_UnitPrice" : string
See Also