A PostgreSQL Interface for SQL Analysis Services Data

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 our JDBC Drivers, you can now create PostgreSQL entry-points that you can connect to from any standard client.

To access SQL Analysis Services data as a PostgreSQL database, use the CData JDBC Driver for SQL Analysis Services and a JDBC foreign data wrapper (FDW). In this article, we compile the FDW, install it, and query SQL Analysis Services data from PostgreSQL Server.

Connect to SQL Analysis Services Data as a JDBC Data Source

To connect to SQL Analysis Services as a JDBC data source, you will need the following:

• Driver JAR path: The JAR is located in the lib subfolder of the installation directory.

• Driver class: cdata.jdbc.ssas.SSASDriver

• JDBC URL: The URL must start with "jdbc:ssas:" and can include any of the connection properties in name-value pairs separated with semicolons.

  To connect, provide authentication and set the Url property to a valid SQL Server Analysis Services endpoint. You can connect to SQL Server Analysis Services instances hosted over HTTP with XMLA access. See the Microsoft documentation to configure HTTP access to SQL Server Analysis Services.

  To secure connections and authenticate, set the corresponding connection properties, below. The data provider supports the major authentication schemes, including HTTP and Windows, as well as SSL/TLS.

  • HTTP Authentication

    Set AuthScheme to "Basic" or "Digest" and set User and Password. Specify other authentication values in CustomHeaders.

  • Windows (NTLM)

    Set the Windows User and Password and set AuthScheme to "NTLM".

  • Kerberos and Kerberos Delegation

    To authenticate with Kerberos, set AuthScheme to NEGOTIATE. To use Kerberos delegation, set AuthScheme to KERBEROSDELEGATION. If needed, provide the User, Password, and KerberosSPN. By default, the data provider attempts to communicate with the SPN at the specified Url.

  • SSL/TLS:

    By default, the data provider attempts to negotiate SSL/TLS by checking the server's certificate against the system's trusted certificate store. To specify another certificate, see the SSLServerCert property for the available formats.

  You can then access any cube as a relational table: When you connect the data provider retrieves SSAS metadata and dynamically updates the table schemas. Instead of retrieving metadata every connection, you can set the CacheLocation property to automatically cache to a simple file-based store.

  See the Getting Started section of the CData documentation, under Retrieving Analysis Services Data, to execute SQL-92 queries to the cubes.

  Built-in Connection String Designer

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

  java -jar cdata.jdbc.ssas.jar

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

  A typical JDBC URL is below:

  jdbc:ssas:User=myuseraccount;Password=mypassword;URL=http://localhost/OLAP/msmdpump.dll;

Build the JDBC Foreign Data Wrapper

The Foreign Data Wrapper can be installed as an extension to PostgreSQL, without recompiling PostgreSQL. The jdbc2_fdw extension is used as an example (downloadable here).

1. Add a symlink from the shared object for your version of the JRE to /usr/lib/libjvm.so. For example: ln -s /usr/lib/jvm/java-6-openjdk/jre/lib/amd64/server/libjvm.so /usr/lib/libjvm.so
2. Start the build: make install USE_PGXS=1

Query SQL Analysis Services Data as a PostgreSQL Database

After you have installed the extension, follow the steps below to start executing queries to SQL Analysis Services data:

1. Log into your database.
2. Load the extension for the database: CREATE EXTENSION jdbc2_fdw;
3. Create a server object for SQL Analysis Services: CREATE SERVER SSAS FOREIGN DATA WRAPPER jdbc2_fdw OPTIONS ( drivername 'cdata.jdbc.ssas.SSASDriver', url 'jdbc:ssas:User=myuseraccount;Password=mypassword;URL=http://localhost/OLAP/msmdpump.dll;', querytimeout '15', jarfile '/home/MyUser/CData/CData\ JDBC\ Driver\ for\ Salesforce MyDriverEdition/lib/cdata.jdbc.ssas.jar');
4. Create a user mapping for the username and password of a user known to the MySQL daemon. CREATE USER MAPPING for postgres SERVER SSAS OPTIONS ( username 'admin', password 'test');
5. Create a foreign table in your local database: postgres=# CREATE FOREIGN TABLE adventure_works ( adventure_works_id text, adventure_works_Fiscal_Year text, adventure_works_Sales_Amount numeric) SERVER SSAS OPTIONS ( table_name 'adventure_works');