ST_IsEmpty(g) IsEmpty(g)
IsEmpty is a function defined by the OpenGIS specification, but is not fully implemented by MariaDB or MySQL.
Since MariaDB and MySQL do not support GIS EMPTY values such as POINT EMPTY, as implemented it simply returns 1
if the geometry value g
is invalid, 0
if it is valid, and NULL
if the argument is NULL
.
ST_IsEmpty()
and IsEmpty()
are synonyms.
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Licensed under the Creative Commons Attribution 3.0 Unported License and the GNU Free Documentation License.
https://mariadb.com/kb/en/isempty/