Because of the presence of the case insensitive collation 'utf8mb4_unicode_ci' in mysql database on the column name for the table icingaweb_user, user_name query column in DbUserBackend is always case insensitive for mysql. And there is no difference between the user (where COLLATE utf8mb4_general_ci seems redundant) and user_name query columns as they are both case insensitive.
And in case of Postgres the case sensitivity works as expected.
But since the user names have case-insensitive uniqueness at the schema level, the case sensitive filter might be redundant for users and either user or user_name query column could be dropped to have consistency across MySQL and PostgreSQL.
Because of the presence of the case insensitive collation 'utf8mb4_unicode_ci' in mysql database on the column
namefor the tableicingaweb_user,user_namequery column in DbUserBackend is always case insensitive for mysql. And there is no difference between theuser(whereCOLLATE utf8mb4_general_ciseems redundant) anduser_namequery columns as they are both case insensitive.And in case of Postgres the case sensitivity works as expected.
But since the user names have case-insensitive uniqueness at the schema level, the case sensitive filter might be redundant for users and either
useroruser_namequery column could be dropped to have consistency across MySQL and PostgreSQL.