ETL Neo4J in Oracle Data Integrator

Leverage existing skills by using the JDBC standard to connect to Neo4J: Through drop-in integration into ETL tools like Oracle Data Integrator (ODI), the CData JDBC Driver for Neo4J connects real-time Neo4J data to your data warehouse, business intelligence, and Big Data technologies.

JDBC connectivity enables you to work with Neo4J just as you would any other database in ODI. As with an RDBMS, you can use the driver to connect directly to the Neo4J APIs in real time instead of working with flat files.

This article walks through a JDBC-based ETL -- Neo4J to Oracle. After reverse engineering a data model of Neo4J entities, you will create a mapping and select a data loading strategy -- since the driver supports SQL-92, this last step can easily be accomplished by selecting the built-in SQL to SQL Loading Knowledge Module.

Install the Driver

To install the driver, copy the driver JAR (cdata.jdbc.neo4j.jar) and .lic file (cdata.jdbc.neo4j.lic), located in the installation folder, into the ODI appropriate directory:

• UNIX/Linux without Agent: ~/.odi/oracledi/userlib
• UNIX/Linux with Agent: ~/.odi/oracledi/userlib and $ODI_HOME/odi/agent/lib
• Windows without Agent: %APPDATA%\Roaming\odi\oracledi\userlib
• Windows with Agent: %APPDATA%\odi\oracledi\userlib and %APPDATA%\odi\agent\lib

Restart ODI to complete the installation.

Reverse Engineer a Model

Reverse engineering the model retrieves metadata about the driver's relational view of Neo4J data. After reverse engineering, you can query real-time Neo4J data and create mappings based on Neo4J tables.

1. In ODI, connect to your repository and click New -> Model and Topology Objects.
2. On the Model screen of the resulting dialog, enter the following information:
   • Name: Enter Neo4j.
   • Technology: Select Generic SQL (for ODI Version 12.2+, select Microsoft SQL Server).
   • Logical Schema: Enter Neo4j.
   • Context: Select Global.
3. On the Data Server screen of the resulting dialog, enter the following information:
   • Name: Enter Neo4j.
   • Driver List: Select Oracle JDBC Driver.
   • Driver: Enter cdata.jdbc.neo4j.Neo4jDriver
   • URL: Enter the JDBC URL containing the connection string.

     To connect to Neo4j, set the following connection properties:

     • Server: The server hosting the Neo4j instance.
     • Port: The port on which the Neo4j service is running. The provider connects to port 7474 by default.
     • User: The username of the user using the Neo4j instance.
     • Password: The password of the user using the Neo4j instance.

     Built-in Connection String Designer

     For assistance in constructing the JDBC URL, use the connection string designer built into the Neo4J JDBC Driver. Either double-click the JAR file or execute the jar file from the command-line.

     java -jar cdata.jdbc.neo4j.jar

     Fill in the connection properties and copy the connection string to the clipboard.

     Below is a typical connection string:

     jdbc:neo4j:Server=localhost;Port=7474;User=my_user;Password=my_password;
4. On the Physical Schema screen, enter the following information:
   • Name: Select from the Drop Down menu.
   • Database (Catalog): Enter CData.
   • Owner (Schema): If you select a Schema for Neo4J, enter the Schema selected, otherwise enter Neo4j.
   • Database (Work Catalog): Enter CData.
   • Owner (Work Schema): If you select a Schema for Neo4J, enter the Schema selected, otherwise enter Neo4j.
5. In the opened model click Reverse Engineer to retrieve the metadata for Neo4J tables.

Edit and Save Neo4J Data

After reverse engineering you can now work with Neo4J data in ODI. To view Neo4J data, expand the Models accordion in the Designer navigator, right-click a table, and click View data.

Create an ETL Project

Follow the steps below to create an ETL from Neo4J. You will load ProductCategory entities into the sample data warehouse included in the ODI Getting Started VM.

1. Open SQL Developer and connect to your Oracle database. Right-click the node for your database in the Connections pane and click new SQL Worksheet.

   Alternatively you can use SQLPlus. From a command prompt enter the following:

   sqlplus / as sysdba
2. Enter the following query to create a new target table in the sample data warehouse, which is in the ODI_DEMO schema. The following query defines a few columns that match the ProductCategory table in Neo4J: CREATE TABLE ODI_DEMO.TRG_PRODUCTCATEGORY (CATEGORYNAME NUMBER(20,0),CategoryId VARCHAR2(255));
3. In ODI expand the Models accordion in the Designer navigator and double-click the Sales Administration node in the ODI_DEMO folder. The model is opened in the Model Editor.
4. Click Reverse Engineer. The TRG_PRODUCTCATEGORY table is added to the model.
5. Right-click the Mappings node in your project and click New Mapping. Enter a name for the mapping and clear the Create Empty Dataset option. The Mapping Editor is displayed.
6. Drag the TRG_PRODUCTCATEGORY table from the Sales Administration model onto the mapping.
7. Drag the ProductCategory table from the Neo4J model onto the mapping.
8. Click the source connector point and drag to the target connector point. The Attribute Matching dialog is displayed. For this example, use the default options. The target expressions are then displayed in the properties for the target columns.
9. Open the Physical tab of the Mapping Editor and click PRODUCTCATEGORY_AP in TARGET_GROUP.
10. In the PRODUCTCATEGORY_AP properties, select LKM SQL to SQL (Built-In) on the Loading Knowledge Module tab.

You can then run the mapping to load Neo4J data into Oracle.