Posts Tagged ‘ plugins ’

QGIS plugins: RT SQL Layers vs Fast SQL Layer

Two fun plugins for QGIS:  RT SQL Layers and Fast SQL Layer.  They have similar functionality, they let you write your own queries against a PostGIS or Spatialite database and have the results.

First, Fast SQL Layer.  Before you install the plugin it needs a python module, pygments, installed.  This will allow Fast SQL Layer to have syntax highlighting.  For Arch users install the module with pacman:

sudo pacman -S python2-pygments

After that is installed, in QGIS go to the Fetch Python Plugins entry under the Plugins menu, then click the Repositories tab, then click the Add 3rd party plugins button.  Once the repositories are updated you can go back to the first tab and install Fast SQL Layers.

Second is RT SQL Layers Plugin.  To add this plugin you need to point QGIS to the Fanutla plugin repository.  If the Add 3rd party plugins button did not find the repository add it manually by copying the target of the previous link and adding it with the Add button.

Now which one is better?  Personally I think it is a tie.  RT SQL Layers gives you a nice GUI for creating your query, just click on the tables and field you want returned and it formats the query for you.  However, once you click OK its window disappears and unless you copied or saved the query you have to start from scratch.  Fast SQL Layers doesn’t have a GUI, it just gives you a window, by default this window will fit itself below your map, and you type out the query by hand.  However, since the window doesn’t go away and the syntax highlighting is very helpful it is easy to catch mistakes and to tweak queries through several versions without starting from scratch each time.