How do I enter an “empty” POINT() geometry value i

问题:

I have a table with a POINT geometry field. I enter latitude/longitude points into it like this:

INSERT INTO table( point )
VALUES( POINT( lon_value, lat_value );

Sometimes I do not have lat/lon values to enter. I am unable to enter a blank, a NULL, or an empty POINT() ... since POINT(0,0) is actually a location on the globe, that won't work either.

What is the solution here?

回答1:

I would use coordinates of North Pole

INSERT INTO table( point )
VALUES( POINT(0.0000,90.0000);

If the actual coordinates of the pole may be an issue i would change the lon value from 0.0000.

回答2:

Only GeometryCollection supports EMPTY: https://dev.mysql.com/doc/refman/8.0/en/gis-data-formats.html

INSERT INTO table( point )
VALUES( ST_GeomFromText('GEOMETRYCOLLECTION EMPTY') );