Why does one of the following notations print a readable string, (100,200) whereas the others show a binary format?

SELECT geography 'POINT(100 200)', 
       point '100,200', 
       geography(point) 'POINT(100 200)'

https://dbfiddle.uk/?rdbms=postgres_14&fiddle=1cd06e002ab74b70189f908cafb7e17b

CodePudding user response：

geometry and geography are geographic data types from the extension PostGIS and point is a PosgreSQL geometric data type. If you're planing to store latitude and longitude values I suggest you to use PostGIS, as it provides plenty of handy functions out of the box.

The binary value you're seeing is a WKB (well known binary) representation of the geometry - standard representation. There are many other ways to serialize geometries.