Ready to get started?

Learn more about the CData JDBC Driver for CSV or download a free trial:

Download Now

JRuby からCSV Data にデータ連携

リアルタイムCSV data に連携するシンプルなJRuby アプリケーションを作成します。

JRuby はRuby プログラミング言語の高性能で安定した、完全にスレッド化されたJava 実装です。CData JDBC Driver for CSV を使用すると、JRuby からリアルタイムCSV data へのデータ連携を簡単に実装できます。ここでは、CSV data に接続し、クエリを実行して結果を表示する簡単なJRuby アプリを作成する方法を説明します。

CSV Data にJDBC で接続

Before creating the app, note the installation location for the JAR file for the JDBC Driver (typically C:\Program Files\CDatat\CData JDBC Driver for CSV\lib).

JRuby natively supports JDBC, so you can easily connect to CSV and execute SQL queries.Initialize the JDBC connection with the getConnection function of the java.sql.DriverManager class.

The DataSource property must be set to a valid local folder name.

Also, specify the IncludeFiles property to work with text files having extensions that differ from .csv, .tab, or .txt. Specify multiple file extensions in a comma-separated list. You can also set Extended Properties compatible with the Microsoft Jet OLE DB 4.0 driver. Alternatively, you can provide the format of text files in a Schema.ini file.

Set UseRowNumbers to true if you are deleting or updating in CSV. This will create a new column with the name RowNumber which will be used as key for that table.

ビルトイン接続文字列デザイナー

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

java -jar cdata.jdbc.csv.jar

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

Below is a typical JDBC connection string for CSV:

jdbc:csv:DataSource=MyCSVFilesFolder;

CSV Data への接続性を持つJRuby アプリを作成

Create a new Ruby file (for example: CSVSelect.rb) and open it in a text editor.Copy the following code into your file:

require 'java' require 'rubygems' require 'C:/Program Files/CData/CData JDBC Driver for CSV 2018/lib/cdata.jdbc.csv.jar' url = "jdbc:csv:DataSource=MyCSVFilesFolder;" conn = java.sql.DriverManager.getConnection(url) stmt = conn.createStatement rs = stmt.executeQuery("SELECT City, TotalDue FROM Customer") while (rs.next) do puts rs.getString(1) + ' ' + rs.getString(2) end

With the file completed, you are ready to display your CSV data with JRuby.To do so, simply run your file from the command line:

jruby -S CSVSelect.rb

Writing SQL-92 queries to CSV allows you to quickly and easily incorporate CSV data into your own JRuby applications.Download a free trial today!

 
 
ダウンロード