Useful links

Installation

Building a SQLite3 tcl extension with JSON1 enabled: SQLite extension JSON1 | Tcl Wiki

GNU/Linux Administration

Installation of a free SSL certificates: Certbot on Apache on Debian 8 (Jessie)

Common GIS questions

Description of spatial relations: Spatial Relations Defined

GIS data conversions

Converting CVS WKT data to shape files: How can I convert a csv file of WKT data to a shape file using ogr2ogr?

Client side GIS

Using popups with OL3:Elements that make up the popup

SQL Queries

UPDATE from SELECT How do I UPDATE from a SELECT in SQL Server?