Loading some sample data

To make this chapter a pleasant experience for you, I have compiled some sample data, which has been taken from the BP energy report: http://www.bp.com/en/global/corporate/energy-economics/statistical-review-of-world-energy.html.

Here is the data structure that will be used:

test=# CREATE TABLE t_oil ( 
  region          text,  
  country         text,  
  year            int,  
  production      int,  
  consumption     int 
); 
CREATE TABLE 

The test data can be downloaded from our website using curl directly:

test=# COPY t_oil FROM PROGRAM ' curl www.cybertec.at/secret/oil_ext.txt '; 
COPY 644 

As in the previous chapter, you can download the file before importing it. On some operating systems, curl is not there by default or has not been installed, so downloading the file before might be an easier option for many people.

There is data for 14 nations between 1965 and 2010, which are in two regions of the world:

test=# SELECT region, avg(production) FROM   t_oil GROUP BY region;
    region     |          avg           
---------------+----------------------- 
 Middle East   | 1992.6036866359447005 
 North America | 4541.3623188405797101 
(2 rows)