A PostgreSQL Interface for HCL Domino Data



Use the SQL Gateway and HCL Domino ODBC Driver to create a PostgreSQL entry-point for data access.

There are a vast number of PostgreSQL clients available on the Internet. From standard Drivers to BI and Analytics tools, PostgreSQL is a popular interface for data access. Using the SQL Gateway included in our ODBC Drivers, you can now create PostgreSQL entry-points that you can connect to from any standard client.

To access HCL Domino data as a PostgreSQL database on Windows, use the CData SQL Gateway, the ODBC Driver for HCL Domino, and the MySQL foreign data wrapper from EnterpriseDB. In this article, we compile the foreign data wrapper in Visual Studio, install it as an extension, and query HCL Domino data from PostgreSQL Server.

Configure the Connection to HCL Domino

If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs.

Connecting to Domino

To connect to Domino data, set the following properties:

  • URL: The host name or IP of the server hosting the Domino database. Include the port of the server hosting the Domino database. For example: http://sampleserver:1234/
  • DatabaseScope: The name of a scope in the Domino Web UI. The driver exposes forms and views for the schema governed by the specified scope. In the Domino Admin UI, select the Scopes menu in the sidebar. Set this property to the name of an existing scope.

Authenticating with Domino

Domino supports authenticating via login credentials or an Azure Active Directory OAuth application:

Login Credentials

To authenticate with login credentials, set the following properties:

  • AuthScheme: Set this to "OAuthPassword"
  • User: The username of the authenticating Domino user
  • Password: The password associated with the authenticating Domino user

The driver uses the login credentials to automatically perform an OAuth token exchange.

AzureAD

This authentication method uses Azure Active Directory as an IdP to obtain a JWT token. You need to create a custom OAuth application in Azure Active Directory and configure it as an IdP. To do so, follow the instructions in the Help documentation. Then set the following properties:

  • AuthScheme: Set this to "AzureAD"
  • InitiateOAuth: Set this to GETANDREFRESH. You can use InitiateOAuth to avoid repeating the OAuth exchange and manually setting the OAuthAccessToken.
  • OAuthClientId: The Client ID obtained when setting up the custom OAuth application.
  • OAuthClientSecret: The Client secret obtained when setting up the custom OAuth application.
  • CallbackURL: The redirect URI defined when you registered your app. For example: https://localhost:33333
  • AzureTenant: The Microsoft Online tenant being used to access data. Supply either a value in the form companyname.microsoft.com or the tenant ID.

    The tenant ID is the same as the directory ID shown in the Azure Portal's Azure Active Directory > Properties page.

Start the Remoting Service

The MySQL remoting service is a daemon process that listens for clients' incoming MySQL connections. See the setup guide in the SQL Gateway overview to configure the MySQL Remoting service in the CData SQL Gateway.

Build the MySQL Foreign Data Wrapper

The Foreign Data Wrapper can be installed as an extension to PostgreSQL, without recompiling PostgreSQL. If you are running PostgreSQL on a Unix-based system, you can use the PostgreSQL Extension Network (PGXN) to install the FDW, mysql_fdw. If you are running PostgreSQL on Windows, compile the extension to ensure that you are working with the latest version. Follow the steps below to make the necessary modifications to build the extension from Visual Studio:

Obtain Prerequisites

To build the foreign data wrapper, do the following:

  • Install PostgreSQL. This example uses an installation of PostgreSQL 9.4.
  • If you are using a 64-bit installation of PostgreSQL, obtain libintl.h from the PostgreSQL source. The 64-bit PostgreSQL installer does not currently include libintl.h.
  • Obtain the source for the mysql_fdw foreign data wrapper from EnterpriseDB.
  • Install MySQL Connector C. This example uses an installation of MySQL Connector C 6.1.

Configure a Project

After you have obtained the necessary software and source code, you are ready to compile the extension with Visual Studio. Follow the steps below to create a project using the mysql_fdw source:

  1. In Visual Studio, create a new empty C++ project.
  2. In Solution Explorer, right-click Source Files and click Add -> Existing Item. In the file explorer, select all of the .c and .h files from the mysql_fdw source.

Follow the steps below to configure your project:

  1. If you are building for a 64-bit system, click Build -> Configuration Manager and in Active Solution Platform select x64.
  2. Right-click your project and click Properties.
  3. In the Configuration menu, select All Configurations.
  4. In Configuration Properties -> General -> Configuration Type, select Dynamic Library.
  5. In Configuration Properties -> C/C++ -> Code Generation -> Enable C++ Exceptions, select No.
  6. In Configuration Properties -> C/C++ -> Advanced -> Compile As, select Compile as C Code.
  7. In Linker -> Manifest File -> Generate Manifest, select No.

Follow the steps below to add the required dependencies:

  1. In Linker -> Input -> Additional Dependencies, select Edit and enter the following: postgres.lib libmysql.lib WS2_32.lib Secur32.lib Additionally, ensure that Inherit From Parent or Project Defaults is checked.
  2. In Linker -> General -> Additional Library Directories, select Edit and add the path to the lib folder in your PostgreSQL installation.
  3. In Linker -> General -> Link Library Dependencies, select No.
  4. To complete the configuration of your project, add the necessary includes: In C/C++ -> General -> Additional Include Directories, add the following folders in the following order: MyMySQLConnectorCInstallation\include MyPostgreSQLInstallation\MyPostgreSQLVersion\include\server\port\win32_msvc MyPostgreSQLInstallation\MyPostgreSQLVersion\include\server\port\win32 MyPostgreSQLInstallation\MyPostgreSQLVersion\include\server MyPostgreSQLInstallation\MyPostgreSQLVersion\include

Configure mysql_fdw for Windows

After setting up a project, make the following changes to build mysql_fdw in Visual Studio:

  1. In mysql_fdw.c, add the following defines: #define dlsym(lib, name) (void*)GetProcAddress((HMODULE)lib, name) #define dlopen(libname, unused) LoadLibraryEx(libname, NULL, 0)
  2. In the mysql_load_library definition, delete the following line: mysql_dll_handle = dlopen(_MYSQL_LIBNAME, RTLD_LAZY | RTLD_DEEPBIND);
  3. Add the following line in the mysql_load_library definition to replace the assignment of mysql_dll_handle for a Windows build: mysql_dll_handle = dlopen("libmysql.dll", 0);
  4. Prepend the call to the mysql_fdw_handler function with the __declspec(dllexport) keyword to export the function from the DLL: __declspec(dllexport) extern Datum mysql_fdw_handler(PG_FUNCTION_ARGS);
  5. In option.c, prepend the declaration of the mysql_fdw_validator function with the __declspec(dllexport) keyword to export the function from the DLL: __declspec(dllexport) extern Datum mysql_fdw_validator(PG_FUNCTION_ARGS);

You can now select the Release configuration and build.

Install the Extension

After you have compiled the DLL, follow the steps below to install the extension:

  1. Add the path to the lib folder for MySQL Connector C to the PATH environment variable of the machine running PostgreSQL.
  2. Copy the DLL from the RElease folder for your project into the lib subfolder of your PostgreSQL installation.
  3. In the folder containing the mysql_fdw csource files, copy myswl_fdw--1.0.sql and mysql_fdw.control into the extension folder under the share folder of your PostgreSQL installation. For example: C:\Program Files\PostgreSQL\9.4\share\extension.

Query HCL Domino Data as a PostgreSQL Database

After you have installed the extension, follow the steps below to start executing queries to HCL Domino data:

  1. Log into your PostgreSQL database. For example: C:\> psql -U postgres
  2. Load the extension for the database: postgres=#CREATE EXTENSION mysql_fdw;
  3. Create a server object for HCL Domino data: postgres=# CREATE SERVER Domino FOREIGN DATA WRAPPER mysql_fdw OPTIONS (host '127.0.0.1', port '3306');
  4. Create a user mapping for the username and password of a user known to the MySQL remoting service. Below are the credentials for the user in the sample configuration of the service: postgres=# CREATE USER MAPPING for postgres SERVER Domino OPTIONS (username 'admin', password 'test');
  5. Create the local schema: postgres=# CREATE SCHEMA Domino_db;
  6. Import all the tables in the HCL Domino database you defined: postgres=# IMPORT FOREIGN SCHEMA "CData Domino Sys" FROM SERVER Domino INTO Domino_db;

You can now execute SELECT commands to HCL Domino:

postgres=# SELECT * FROM Domino_db."byname";

Ready to get started?

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HCL Domino Icon HCL Domino ODBC Driver

The HCL Domino ODBC Driver is a powerful tool that allows you to connect with live data from HCL Domino, directly from any applications that support ODBC connectivity.

Access HCL Domino data like you would a database - read, write, and update HCL Domino FALSE, etc. through a standard ODBC Driver interface.