ETL Gmail in Oracle Data Integrator

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

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

This article walks through a JDBC-based ETL -- Gmail to Oracle. After reverse engineering a data model of Gmail 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.gmail.jar) and .lic file (cdata.jdbc.gmail.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 Gmail data. After reverse engineering, you can query real-time Gmail data and create mappings based on Gmail 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 Gmail.
   • Technology: Select Generic SQL (for ODI Version 12.2+, select Microsoft SQL Server).
   • Logical Schema: Enter Gmail.
   • Context: Select Global.
3. On the Data Server screen of the resulting dialog, enter the following information:
   • Name: Enter Gmail.
   • Driver List: Select Oracle JDBC Driver.
   • Driver: Enter cdata.jdbc.gmail.GmailDriver
   • URL: Enter the JDBC URL containing the connection string.

     There are two ways to authenticate to Gmail. Before selecting one, first ensure that you have enabled IMAP access in your Gmail account settings. See the "Connecting to Gmail" section under "Getting Started" in the installed documentation for a guide.

     The User and Password properties, under the Authentication section, can be set to valid Gmail user credentials.

     Alternatively, instead of providing the Password, you can use the OAuth authentication standard. To access Google APIs on behalf on individual users, you can use the embedded credentials or you can register your own OAuth app.

     OAuth also enables you to use a service account to connect on behalf of users in a Google Apps domain. To authenticate with a service account, you will need to register an application to obtain the OAuth JWT values.

     In addition to the OAuth values, you will need to provide the User. See the "Getting Started" chapter in the help documentation for a guide to using OAuth.

     Built-in Connection String Designer

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

     java -jar cdata.jdbc.gmail.jar

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

     Below is a typical connection string:

     jdbc:gmail:User=username;Password=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 Gmail, enter the Schema selected, otherwise enter Gmail.
   • Database (Work Catalog): Enter CData.
   • Owner (Work Schema): If you select a Schema for Gmail, enter the Schema selected, otherwise enter Gmail.
5. In the opened model click Reverse Engineer to retrieve the metadata for Gmail tables.

Edit and Save Gmail Data

After reverse engineering you can now work with Gmail data in ODI. To edit and save Gmail data, expand the Models accordion in the Designer navigator, right-click a table, and click Data. Click Refresh to pick up any changes to the data. Click Save Changes when you are finished making changes.

Create an ETL Project

Follow the steps below to create an ETL from Gmail. You will load Inbox 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 Inbox table in Gmail: CREATE TABLE ODI_DEMO.TRG_INBOX (SIZE NUMBER(20,0),Subject 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_INBOX 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_INBOX table from the Sales Administration model onto the mapping.
7. Drag the Inbox table from the Gmail 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 INBOX_AP in TARGET_GROUP.
10. In the INBOX_AP properties, select LKM SQL to SQL (Built-In) on the Loading Knowledge Module tab.

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