Ruby, ADO, and SQLServer

Ruby and ActiveX Data Objects (ADO) make working with Microsoft SQL Server databases simple. Here's a simple example of a class that manages the SQL Server database connection and queries:

require 'win32ole'

class SqlServer
    # This class manages database connection and queries
    attr_accessor :connection, :data, :fields

    def initialize
        @connection = nil
        @data = nil
    end

    def open
        # Open ADO connection to the SQL Server database
        connection_string =  "Provider=SQLOLEDB.1;"
        connection_string << "Persist Security Info=False;"
        connection_string << "User ID=USER_ID;"
        connection_string << "password=PASSWORD;"
        connection_string << "Initial Catalog=DATABASE;"
        connection_string << "Data Source=IP_ADDRESS;"
        connection_string << "Network Library=dbmssocn"
        @connection = WIN32OLE.new('ADODB.Connection')
        @connection.Open(connection_string)
    end

    def query(sql)
        # Create an instance of an ADO Recordset
        recordset = WIN32OLE.new('ADODB.Recordset')
        # Open the recordset, using an SQL statement and the
        # existing ADO connection
        recordset.Open(sql, @connection)
        # Create and populate an array of field names
        @fields = []
        recordset.Fields.each do |field|
            @fields << field.Name
        end
        begin
            # Move to the first record/row, if any exist
            recordset.MoveFirst
            # Grab all records
            @data = recordset.GetRows
        rescue
            @data = []
        end
        recordset.Close
        # An ADO Recordset's GetRows method returns an array 
        # of columns, so we'll use the transpose method to 
        # convert it to an array of rows
        @data = @data.transpose
    end

    def close
        @connection.Close
    end
end

You can then use this class as follows:

db = SqlServer.new
db.open
db.query("SELECT PLAYER FROM PLAYERS WHERE TEAM = 'REDS';")
field_names = db.fields
players = db.data
db.close

The above code is, of course, incomplete and can certainly be improved and extended (error handling, etc.). But, hopefully, it provides you with a solid foundation on which to build.

UPDATE: You might like to know that you can automate many of your SQL Server administrative tasks by leveraging Distributed Management Objects (SQL-DMO). I've explained this in a later article here.

Thanks for stopping by!