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Hierarchy Builder transformation example

You want to convert relational data to hierarchical data and write the data to a target file in a hierarchical format.
To use the Hierarchy Builder transformation to convert the data, complete the following steps:
  1. 1Create a hierarchical schema.
  2. 2Create a mapping.
  3. 3Configure the Hierarchy Builder transformation.
  4. 4Configure the target.
  5. 5Run the mapping.

Step 1. Create a hierarchical schema

You need to configure a hierarchical schema that uses a schema file to define the hierarchy of the output data.
The following example shows the schema hierarchy that you want to use:
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns="http://www.itemfield.com" targetNamespace="http://www.itemfield.com" elementFormDefault="qualified">
<xs:element name="Employees">
<xs:complexType>
<xs:sequence>
<xs:element name="Name" type="xs:string" minOccurs="0"/>
<xs:element name="Address" type="xs:string" minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="Employee" minOccurs="1" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:element name="EmployeeID" type="xs:string" minOccurs="0"/>
<xs:element name="Department" type="xs:string" minOccurs="0"/>
<xs:element name="Subdivision" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:element name="Building" type="xs:string" minOccurs="0"/>
<xs:element name="Room" type="xs:string" minOccurs="0"
maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
The following example shows the first input file data that you want to use:
CompanyName,Address
First National Bank,874 Louis Road
Jackson Industry,13 Sydney Drive
The following example shows the second input file data that you want to use:
Name,EmployeeID,Department,Building,Room
First National Bank,122,Credit,6,1532
First National Bank,261,Credit,6,2251
First National Bank,431,Credit,6,5312
Jackson Industry,3875,Manufacture,C,673
Jackson Industry,2837,Manufacture,B,211
Create the hierarchical schema in Data Integration with the schema hierarchy that you want to use.

Step 2. Create a mapping

To parse the input data, use a Hierarchy Builder transformation in a mapping to transform the data from the hierarchical input.
In the Mapping Designer, you add two source objects that are flat files that contain the paths to the data files that you want to parse. The following image shows one of the Source transformations:
The source object details show the the connection, type of source, and the input file.

Step 3. Configure the Hierarchy Builder transformation

You add an Hierarchy Builder transformation and use the name NewHierarchyBuilder. Configure it to use the hierarchical schema that you created.
You connect the source objects to the NewHierarchyBuilder transformation. To map the incoming data to the fields of the transformation, select the NewHierarchyBuilder transformation. In the Incoming Fields tab, ensure that there are no field name conflicts. The following image shows the input field selection:
The Field Mapping tab shows the incoming fields that you can map to the Structure Parser input fields.
To map the relational fields to the hierarchical output, in the Field Mapping tab, select primary and foreign keys. Then select which relational fields are linked to schema elements for the hierarchical output.
The following image shows the field mapping selection:

Step 4. Configure the target

Add a file target object for the fields.
The following image shows the final mapping:
The mapping shows the data flow from the SourceLogFile source to a Structure Parser transformation with name LogParser. The Structure Parser transformations is linked to the TargetFile target.

Step 5. Run the mapping

Run the mapping to write the data in a hierarchical format to the Target transformation.
The following example shows the hierarchical output:
<Employees>
<Name>First National Bank</Name>
<Address>874 Louis Road</Address>
<Employee>
<EmployeeID>122</EmployeeID>
<Department>Credit</Department>
<Subdivision>
<Building>6</Building>
<Room>1532</Room>
</Subdivision>
</Employee>
<Employee>
<EmployeeID>261</EmployeeID>
<Department>Credit</Department>
<Subdivision>
<Building>6</Building>
<Room>2251</Room>
</Subdivision>
</Employee>
<Employee>
<EmployeeID>431</EmployeeID>
<Department>Credit</Department>
<Subdivision>
<Building>6</Building>
<Room>5312</Room>
</Subdivision>
</Employee>
</Employees>
<Employees>
<Name>Jackson Industry</Name>
<Address>13 Sydney Drive</Address>
<Employee>
<EmployeeID>3875</EmployeeID>
<Department>Manufacture</Department>
<Subdivision>
<Building>C</Building>
<Room>673</Room>
</Subdivision>
</Employee>
<Employee>
<EmployeeID>2837</EmployeeID>
<Department>Manufacture</Department>
<Subdivision>
<Building>B</Building>
<Room>211</Room>
</Subdivision>
</Employee>
</Employees>