Question

Does anyone ever use MySQL spatial buffer function successfully?
I’ve read the documentation here: http://dev.mysql.com/doc/refman/5.0/en/functions-that-create-new-geometries-from-existing-ones.html#function_buffer

As stated in the documentation, buffer function has 2 parameters. The first one is geometry typed, the second one is distance.

I’ve try to make a geometry variable

mysql> set @g1 = geomfromtext('POINT(1 1)');
Query OK, 0 rows affected (0.00 sec)

Then, to ensure that my variable is correctly set, I perform a query. If the variable not correctly set, such a query will return NULL. In this case, it is confirmed that my variable is correctly set

mysql> select astext(@g1);
+-------------+
| astext(@g1) |
+-------------+
| POINT(1 1)  |
+-------------+
1 row in set (0.00 sec)

I run a query to select a buffer as stated in documentation

mysql> select astext(buffer(@g1, 5));
ERROR 1305 (42000): FUNCTION module_devel.buffer does not exist

Do I miss something here?

EDIT Sorry guys, I think I miss this:

12.17.5.3.2. Spatial Operators

OpenGIS proposes a number of other functions that can produce
geometries. They are designed to implement spatial operators.
These functions are not implemented in MySQL.

Answer 1

This is related to this bug report maybe. Which MySQL server are you using? Maybe you should upgrade to 5.6.