6 Get Started with Connection Groups

A connection group, also known as a Zeppelin interpreter set, is a collection of database connections.

About Connection Groups

In the Connection Group page, a user with Administrator role can manage your connections that constitute the connection group.

You can Edit, and Stop one or more connections that are listed under a connection group in this page.


Only an Administrator user can manage connection groups.
The following information about the connections are available:
  • Name: This is the name of the interpreter.

  • Default: A check mark indicates whether the connection is the default connection or not.

  • Scope: Indicates the scope of the connection.

  • Comment: Displays any comment related to the interpreter.

  • Owner: Displays the name of the user who created the connection.

  • Last Updated: Indicates the date and time when the connection was last updated.

You can perform the following tasks:
  • Edit: To edit the interpreter connection, select the connection and click Edit.

  • Stop: To stop the interpreter connection, select the connection and click Stop.

  • Refresh: Click the Refresh button in the following conditions:
    • If you rename the Pluggable Database (PDB).
    • If you do a Wallet rotation. Wallet rotation invalidates the current wallet. Hence, a new Wallet is needed for the database connection.

About Global Connection Group

The Global Connection Group is created automatically when a new database is provisioned.

The Global Connection Group comprises the following:
  • Compute Resource definition — A Compute Resource is associated with the Pluggable Database (PDB). After a new PDB is provisioned, a Compute Resource is added for the PDB. A tenant may provision more than one PDB, and for each PDB a Compute Resource is added. The settings in the Compute Resource are relevant to its own PDB. The Compute Resource is associated to an Oracle Wallet. The Oracle wallet contains the credentials to connect to the user PDB.


    The Compute Resource definition can be edited by the Administrator only.
  • Connection Group definition — The Global Connection Group comprises a single connection of type Global. Only one Global Connection Group for each Compute Resource is allowed per PDB. No password is required for this connection as it uses the Wallet containing the credentials for the PDB. The Wallet is associated to the Compute Resource.


    A Global Connection Group can be edited by the Administrator only.

    Reset: To reset the interpreter connection, click the connection group name. The connection group opens in a separate page, listing all the interpreter connections in the group. Select the connection you want to reset and click Reset. When you click Reset, then all connections supported by the interpreter are closed, and all notebooks using that connection are cancelled.


    The Reset option is available only to the Administrator.

Edit Oracle Database Interpreter Connection

When defining an Oracle Database interpreter connection, a reference to a compute resource is created. This reference contains all connection-related information about the interpreter.

Compute Resources for an Oracle Database interpreter is defined by your service. You can edit the following:


You must have the Administrator role to edit these fields.
  1. Name: You can edit the name of the interpreter editor here. This is useful if you have several definitions of the same interpreter type in the same interpreter set. By specifying a name, you can turn on or turn off the specific binding to a notebook.
  2. Type: This is a non-editable field. It indicates the connection type
  3. Binding Mode: This is a non-editable field. It defines the behavior of the interpreter instance in memory, and how the resources are shared. By default, the Binding Mode of the Global Connection Group is set to Scoped. It ensures that each notebook creates a new interpreter instance in the same interpreter process.
  4. Row Render Limit: This determines the number of rows to be displayed in the paragraph results when fetching a data structure that can be presented as a table or graph using the Zeppelin built-in plotting service. You must consider the browser capabilities when modifying this setting. The default limit is 1000.


    Zeppelin plotting service works with data that is fetched previously to the client-side for a snapper UI.
  5. Comments: Enter any information related to the interpreter not exceeding 1000 characters.


    You must have Administrator role to edit this field.
  6. In the Compute Resource section, the Resources field indicates the priority of the compute resource. This is a non-editable field.
  7. In the Database section, you can specify additional settings related to PL/SQL DBMS output. Select Enabled to allow the PL/SQL interpreter to display the messages sent to the DBMS_OUTPUT in the paragraph results.
  8. Click Save.