How to create SAS Data Sets federated tables in MySQL

You can use the SQL Gateway to configure a MySQL remoting service and set up federated tables for SAS Data Sets data. The service is a daemon process that provides a MySQL interface to the CData ODBC Driver for SAS Data Sets: After you have started the service, you can create a server and tables using the FEDERATED Storage Engine in MySQL. You can then work with SAS Data Sets data just as you would local MySQL tables.

Connect to SAS Data Sets Data

If you have not already done so, provide values for the required connection properties in the data source name (DSN). You can use the built-in Microsoft ODBC Data Source Administrator to configure the DSN. This is also the last step of the driver installation. See the "Getting Started" chapter in the help documentation for a guide to using the Microsoft ODBC Data Source Administrator to create and configure a DSN.

Set the following connection properties to connect to your SAS DataSet files:

Connecting to Local Files

• Set the Connection Type to "Local." Local files support SELECT, INSERT, and DELETE commands.
• Set the URI to a folder containing SAS files, e.g. C:\PATH\TO\FOLDER\.

Connecting to Cloud-Hosted SAS DataSet Files

While the driver is capable of pulling data from SAS DataSet files hosted on a variety of cloud data stores, INSERT, UPDATE, and DELETE are not supported outside of local files in this driver.

Set the Connection Type to the service hosting your SAS DataSet files. A unique prefix at the beginning of the URI connection property is used to identify the cloud data store and the remainder of the path is a relative path to the desired folder (one table per file) or single file (a single table). For more information, refer to the Getting Started section of the Help documentation.

Configure the SQL Gateway

See the SQL Gateway Overview to set up connectivity to SAS Data Sets data as a virtual MySQL database. You will configure a MySQL remoting service that listens for MySQL requests from clients. The service can be configured in the SQL Gateway UI.

Create a FEDERATED Server and Tables for SAS Data Sets Data

After you have configured and started the service, create a FEDERATED server to simplify the process of creating FEDERATED tables:

Create a FEDERATED Server

The following statement will create a FEDERATED server based on the ODBC Driver for SAS Data Sets. Note that the username and password of the FEDERATED server must match a user account you defined on the Users tab of the SQL Gateway.

CREATE SERVER fedSASDataSets
FOREIGN DATA WRAPPER mysql
OPTIONS (USER 'sql_gateway_user', PASSWORD 'sql_gateway_passwd', HOST 'sql_gateway_host', PORT ####, DATABASE 'CData SASDataSets Sys');

Create a FEDERATED Table

To create a FEDERATED table using our newly created server, use the CONNECTION keyword and pass the name of the FEDERATED server and the remote table (restaurants). Refer to the following template for the statement to create a FEDERATED table:

CREATE TABLE fed_restaurants (
  ...,
  name  TYPE(LEN),
  borough  TYPE(LEN),
  ...,
)
ENGINE=FEDERATED
DEFAULT CHARSET=latin1
CONNECTION='fedSASDataSets/restaurants';

NOTE: The table schema for the FEDERATED table must match the remote table schema exactly. You can always connect directly to the MySQL remoting service using any MySQL client and run a SHOW CREATE TABLE query to get the table schema.

Execute Queries

You can now execute queries to the SAS Data Sets FEDERATED tables from any tool that can connect to MySQL, which is particularly useful if you need to JOIN data from a local table with data from SAS Data Sets. Refer to the following example:

SELECT 
  fed_restaurants.name, 
  local_table.custom_field 
FROM 
  local_table 
JOIN 
  fed_restaurants 
ON 
  local_table.foreign_name = fed_restaurants.name;