database - Can I trust MariaDB Galera cluster unique key -

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consider following table structure in mariadb galera cluster:

create table test (   `name` varchar(100) not null,   `master` tinyint(1) default null,   primary key (`name`),   unique key `master` (`master`) ) engine=innodb;

if running on cluster several nodes, , in parallell do:

insert test (name, master) values('node1', 1);

and on node

insert test (name, master) values('node2', 1);

can trust 1 query not replace other?

if both queries ran @ same time, 1 of them still return error?

if query not return error, can trust no other insert can replace row name?

the unique constraint enforced. galera uses optimistic locking , i'm not sure if query gets cluster second return normal duplicate entry error or different error transaction conflict 1 inserted.


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