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Brainfurnace

We’re please to announce that brainfurnace.com has been acquired by MapFig, Inc.

While we will continue to focus on PostgreSQL solutions, we will also be expanding our support staff as well as our services.

Stay tuned!

WWW Foreign Data Wrapper

This post will review installing and basic usage of the WWW Foreign Data Wrapper.

We will install the FDW and then create a foreign table and query it.

We have created a database called acugrss_wwwexample.  

Step 1: Log into cPanel and, under Foreign Data Wrappers, click the WWW icon.

install

 

Step 2: Click on the “Install fdw_www” link for the target database.

 

install2

 

Step 3: Connect via SSH to your target database (acugrss_wwwexample) in our case:


acugrss@acugres.com [~]# psql -d acugrss_wwwexample 
Password: psql (9.3.5) Type "help" for help. 
acugrss_wwwexample=>

  
Step 4: Following the example from the docs at https://github.com/cyga/www_fdw/wiki/Documentation, we will create a server using the Google Search API:

 


acugrss_wwwexample=> CREATE SERVER www_fdw_google_search_server FOREIGN DATA WRAPPER www_fdw OPTIONS (uri 'https://ajax.googleapis.com/ajax/services/search/web?v=1.0');

This should return “CREATE SERVER”
 
Step 5: Now, we will create a mapping for the user:

CREATE USER MAPPING FOR acugrss SERVER www_fdw_google_search_server;

This should return “CREATE USER MAPPING”
 
Step 6: Finally, we create our foreign table:


CREATE FOREIGN TABLE www_fdw_google_search (
  title text,
  link text,
  snippet text,
  q text /* used for easy query specifying */
) SERVER www_fdw_google_search_server;

 
This should return “CREATE FOREIGN TABLE”
 
We can now query using our foreign table:


select title,snippet from www_fdw_google_search where q='PostgreSQL' limit 3;

Which returns:
 


acugrss_wwwexample=> select title,snippet from www_fdw_google_search where q='PostgreSQL' limit 3;
                                 title                                 | snippet

-----------------------------------------------------------------------+--------
-
 <b>PostgreSQL</b>: The world&#39;s most advanced open source database |
 <b>PostgreSQL</b>: Downloads                                          |
 <b>PostgreSQL</b>: Documentation                                      |
(3 rows)


 

Learn more about www_fdw at https://github.com/cyga/www_fdw/wiki/Documentation

If you need assistance, create a support ticket and we are here to assist.

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