How coordinates are stored in a PostgreSQL/PostGIS database? If not adjusted manually, is it "infinite"? Or up to some digits(15?).

My question is the following: If I work in a PostGIS database with "infinite" precision how is saving a layer as a shapefile or a feature class, process it and then paste it back to the PostGIS database, is going to affect my topology checklist? (for example exactly same nodes in a line segment).

And what would you do if you were to move from PostGIS and back regarding the precision and tolerance of your layer?

  • 6
    There isn't really any such thing as "infinite" coordinate precision. Shapefile and PostGIS use 64-bit IEEE floating-point representation. File geodatabase uses compressed integer as described in the Understanding Coordinate Management in the Geodatabase whitepaper (internally, though the coordinates are exposed in 64-bit float) Furthermore, any geometry processed via ArcGIS will also have the compressed integer geometry rules applied. You'd need to provide a more concrete data flow to determine topology impact.
    – Vince
    Commented Jun 11, 2019 at 16:23
  • @Vince That reads like an excellent answer to the question... Commented Jun 11, 2019 at 20:10
  • As per the Tour there should be only one question asked per question.
    – PolyGeo
    Commented Jun 11, 2019 at 20:39