CREATE TABLE t1(a int) ENGINE=EXAMPLE;
Warnings:
Error	1286	Unknown table engine 'EXAMPLE'
DROP TABLE t1;
INSTALL PLUGIN example SONAME 'ha_example.so';
INSTALL PLUGIN EXAMPLE SONAME 'ha_example.so';
ERROR HY000: Function 'EXAMPLE' already exists
UNINSTALL PLUGIN example;
INSTALL PLUGIN example SONAME 'ha_example.so';
CREATE TABLE t1(a int) ENGINE=EXAMPLE;
SELECT * FROM t1;
a
DROP TABLE t1;
UNINSTALL PLUGIN non_exist;
ERROR 42000: PLUGIN non_exist does not exist