As with most programming languages there are certain types of data -- your fields are dependent on these types and accidental mismatches will result in unpredictable behavior
‘H’ “Hello” “Hello World”
45 54.4 0.0004
10/01/21 04:30:30 2022-08-01 14:00:00
{"k1": "value", "k2": 10}
CREATE TABLE geom (g GEOMETRY NOT NULL SRID 4326);