optiq-csv

Calcite adapter that reads CSV files.

Optiq-csv is a nice simple example of how to connect Apache Calcite to your own data source and quickly get a full SQL/JDBC interface.

Download and build

You need Java (1.6 or higher; 1.7 preferred), git and maven (3.0.4 or later).

$ git clone git://github.com/julianhyde/optiq-csv.git
$ cd optiq-csv
$ mvn compile

Kick the tires

Let's take a quick look at optiq-csv's (and Calcite's) features. We'll use sqlline, a SQL shell that connects to any JDBC data source and is included with optiq-csv.

Connect to Calcite and try out some queries:

$ ./sqlline
sqlline> !connect jdbc:calcite:model=target/test-classes/model.json admin admin
sqlline> !tables
sqlline> !describe emps
sqlline> SELECT * FROM emps;
sqlline> EXPLAIN PLAN FOR SELECT * FROM emps;
sqlline> !connect jdbc:calcite:model=target/test-classes/smart.json admin admin
sqlline> EXPLAIN PLAN FOR SELECT * FROM emps;
sqlline> SELECT depts.name, count(*)
. . . .> FROM emps JOIN depts USING (deptno)
. . . .> GROUP BY depts.name;
sqlline> VALUES char_length('hello, ' || 'world!');
sqlline> !quit

(On Windows, the command is sqlline.bat.)

As you can see, Calcite has a full SQL implementation that can efficiently query any data source.

For a more leisurely walk through what Calcite can do and how it does it, try the Tutorial.

More information

• License: Apache License, Version 2.0.
• Author: Julian Hyde
• Blog: http://julianhyde.blogspot.com
• Project page: http://www.hydromatic.net/optiq-csv
• Source code: http://github.com/julianhyde/optiq-csv
• Developers list: http://mail-archives.apache.org/mod_mbox/incubator-calcite-dev/
• Tutorial
• Release notes and history