Comments in SQL

I have found the following problem:
When in a SQL-Statement there is a commentline and between the '--' and the text there is no ein space, then I get the error ERROR 1064 (42000)....

e.g.

select *

 from information_schema.columns

where TABLE_NAME = 'ALL_PLUGINS'

--and data_type = 'varchar'

;

Error:
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'and data_type = 'varchar'' at line 4

select *

 from information_schema.columns

where TABLE_NAME = 'ALL_PLUGINS'

-- and data_type = 'varchar'

;

then I get no error and get the correct result.