MySQL 8.0 Release Notes
MySQL 8.0 Source Code Documentation
The ST_UNITS_OF_MEASURE table
(available as of MySQL 8.0.14) provides information about
acceptable units for the
ST_Distance() function.
The ST_UNITS_OF_MEASURE table has
these columns:
UNIT_NAMEThe name of the unit.
UNIT_TYPEThe unit type (for example,
LINEAR).CONVERSION_FACTORA conversion factor used for internal calculations.
DESCRIPTIONA description of the unit.