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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

Declaration

public TransformationNodeBuilder FlattenColumn(
    string columnName,
    string alias
)

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
        }
    }
]
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 }
};

The following schema is the result of the transformation:

"ProductID": int
"Info_Name": string
"Info_UnitPrice": string 
See Also