Analyze SQL Analysis Services Data in R via ODBC

Access SQL Analysis Services data with pure R script and standard SQL. You can use the CData ODBC Driver for SQL Analysis Services and the RODBC package to work with remote SQL Analysis Services data in R. By using the CData Driver, you are leveraging a driver written for industry-proven standards to access your data in the popular, open-source R language. This article shows how to use the driver to execute SQL queries to SQL Analysis Services data and visualize SQL Analysis Services data in R.

Install R

You can complement the driver's performance gains from multi-threading and managed code by running the multithreaded Microsoft R Open or by running R linked with the BLAS/LAPACK libraries. This article uses Microsoft R Open (MRO).

Connect to SQL Analysis Services as an ODBC Data Source

Information for connecting to SQL Analysis Services follows, along with different instructions for configuring a DSN in Windows and Linux environments.

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.

When you configure the DSN, you may also want to set the Max Rows connection property. This will limit the number of rows returned, which is especially helpful for improving performance when designing reports and visualizations.

Windows

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.

Linux

If you are installing the CData ODBC Driver for SQL Analysis Services in a Linux environment, the driver installation predefines a system DSN. You can modify the DSN by editing the system data sources file (/etc/odbc.ini) and defining the required connection properties.

/etc/odbc.ini

[CData SSAS Source]
Driver = CData ODBC Driver for SQL Analysis Services
Description = My Description
User = myuseraccount
Password = mypassword
URL = http://localhost/OLAP/msmdpump.dll

For specific information on using these configuration files, please refer to the help documentation (installed and found online).

Load the RODBC Package

To use the driver, download the RODBC package. In RStudio, click Tools -> Install Packages and enter RODBC in the Packages box.

After installing the RODBC package, the following line loads the package:

library(RODBC)

Note: This article uses RODBC version 1.3-12. Using Microsoft R Open, you can test with the same version, using the checkpoint capabilities of Microsoft's MRAN repository. The checkpoint command enables you to install packages from a snapshot of the CRAN repository, hosted on the MRAN repository. The snapshot taken Jan. 1, 2016 contains version 1.3-12.

library(checkpoint)
checkpoint("2016-01-01")

Connect to SQL Analysis Services Data as an ODBC Data Source

You can connect to a DSN in R with the following line:

conn <- odbcConnect("CData SSAS Source")

Schema Discovery

The driver models SQL Analysis Services APIs as relational tables, views, and stored procedures. Use the following line to retrieve the list of tables:

sqlTables(conn)

Execute SQL Queries

Use the sqlQuery function to execute any SQL query supported by the SQL Analysis Services API.

adventure_works <- sqlQuery(conn, "SELECT Fiscal_Year, Sales_Amount FROM Adventure_Works", believeNRows=FALSE, rows_at_time=1)

You can view the results in a data viewer window with the following command:

View(adventure_works)

Plot SQL Analysis Services Data

You can now analyze SQL Analysis Services data with any of the data visualization packages available in the CRAN repository. You can create simple bar plots with the built-in bar plot function:

par(las=2,ps=10,mar=c(5,15,4,2))
barplot(adventure_works$Sales_Amount, main="SQL Analysis Services Adventure_Works", names.arg = adventure_works$Fiscal_Year, horiz=TRUE)

👁 A basic bar plot. (Salesforce is shown.)