In the USER management operation, when the hostname is not specified, it cannot be automatically set to%

mysql>create user yejr identified by 'xx';  -- hostname  is not specified, treated as%
Query OK, 0 rows affected (0.12 sec)

mysql>show grants for yejr;  -- hostname  is not specified, treated as%
+----------------------------------+
| GRANTS FOR 'YEJR'@'%'            |
+----------------------------------+
| GRANT USAGE ON *.* TO 'yejr'@'%' |
+----------------------------------+
1 row in set (1.45 sec)

mysql>set password for yejr = password('xx');  -- hostname  is not specified, errors raised
ERROR 3009 (HY000): [154bfc7d7e002000][172.17.0.6:58709][d3]class com.alibaba.polardbx.druid.sql.ast.expr.SQLIdentifierExpr cannot be cast to class com.alibaba.polardbx.druid.sql.dialect.mysql.ast.expr.MySqlUserName (com.alibaba.polardbx.druid.sql.ast.expr.SQLIdentifierExpr and com.alibaba.polardbx.druid.sql.dialect.mysql.ast.expr.MySqlUserName are in unnamed module of loader 'app')

mysql>set password for yejr@'%' = password('xx');
Query OK, 0 rows affected (0.06 sec)

Start by reproducing the shown CREATE USER, SHOW GRANTS, and SET PASSWORD statements, comparing the hostname-omitted and explicit '%' forms. Trace the SQL handling for SET PASSWORD when the user has no hostname; done means the omitted-hostname form succeeds and behaves like the explicit '%' form.