The tutorials I've been seeing such as this one https://saarapakarinen.wordpress.com/2015/06/13/tutorial-creating-a-postgis-database-for-qgis-part-2/
They mention a SPIT plugin that I can't find anywhere even after installing the WIEN version. DB Manager doesn't quite seem to do the same thing as described in the link above
Is there some other plugin to do the job?