[Documentation] GIS stuff

[sf-dcp]

Motivation

Inspired by issue #449, I would like to aggregate high level information into a markdown file (or a potential blog?) about:

• GIS vocab: features, feature classes, attributes, layers, etc.
• Geodabase VS shapefile
• What is a projection and some examples of it?
• What is a spatial reference?
• wkb vs wkt
• Current workflow in DE & GIS when working with projections

This doc will serve as a reference for us & future staff.

[damonmcc]

my notes from 12/28 coding caucus on File Geodatabases

• vocab
  • feature: a single row with geometry
  • feature class: a collection of features
  • FGDB: File Geodatabase
• FGDB qualities
  • is a container
  • has feature classes
  • has top-level and feature-class-level metadata
  • GeoPackage is an open-source alternative
• GIS currently
  • edits FGDB feature class metadata by exporting, editing, importing XML
  • moving toward single-table outputs like Shapefiles, so FGDBs with a single table
• DE is likely to start editing FGDBs
  • to apply/modify metadata
  • can gdal do it well?
  • python packages
    • arcpy requires a license, arcgis does not need a license
• Pluto example
  • GIS doesn’t really split up tables DE gives them
• Housing DB example
  • multiple tables packaged into one FGDB
• Facilities DB example
  • why an FGDB is better than shapefile
    • shapefile is lossy (nulls, immutable columns, …)
    • better for intermediate