TransformationNodeBuilder.FlattenColumn(String, String) Method

Creates individual columns from the fields of the specified column and prefixes the names of the new columns with the specified alias.

Namespace: DevExpress.DataAccess.DataFederation

Assembly: DevExpress.DataAccess.v21.1.dll

NuGet Packages: DevExpress.DataAccess, DevExpress.Win.Design

Declaration

C#

public TransformationNodeBuilder FlattenColumn(
    string columnName,
    string alias
)

VB.NET

Public Function FlattenColumn(
    columnName As String,
    alias As String
) As TransformationNodeBuilder

Parameters

Name	Type	Description
columnName	String	The name of a column that should be flattened.
alias	String	A prefix to be added to the name of each new column.

Returns

Type	Description
TransformationNodeBuilder	The result of the transformation query.

Example

The following example demonstrates how to flatten a data source’s ProductInfo column and specify a new name for this column.

Show JSON Data

[
    {
        "ProductID": 1,
        "ProductInfo":
        {
            "Name": "Chai",
            "UnitPrice": 18
        }
    },
    {
        "ProductID": 2,
        "ProductInfo":
        {
            "Name": "Chang",
            "UnitPrice": 19
        }
    }
]

C#

using DevExpress.DataAccess.DataFederation;
using DevExpress.DataAccess.Json;
// ...
var source = new Source("Products", jsonDataSource);

var query = source
    .Transform()
    .FlattenColumn("ProductInfo", "Info")
    .Build("ProductsFlattened");

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

VB.NET

Imports DevExpress.DataAccess.DataFederation
Imports DevExpress.DataAccess.Json
' ...
Dim source = New Source("Products", jsonDataSource)

Dim query = source.
    Transform().
    FlattenColumn("ProductInfo", "Info").
    Build("ProductsFlattened")

Dim federation = New FederationDataSource()
federation.Queries.Add(query)

The following schema is the result of the transformation:

"ProductID": int
"Info_Name": string
"Info_UnitPrice": string