The table is cleared after restarting MySQL

it looks like a “engine” has been selected for this table under the name memory (i.e., the table is stored in memory).

you can specify, for example, with the command:

 > show create table имя_таблицы; 

It will be shown exactly which sql command “creates” this table. example output:

 ... ... create table `имя_таблицы` (...) engine=название_движка ... 

You can see a list of all engines supported by your instance of mysqld , for example, like this:

 > show engines; 

example output:

 +--------------------+---------+- | Engine | Support | +--------------------+---------+- | MRG_MYISAM | YES | | CSV | YES | | MyISAM | YES | | BLACKHOLE | YES | | MEMORY | YES | | InnoDB | DEFAULT | | ARCHIVE | YES | | PERFORMANCE_SCHEMA | YES | | FEDERATED | NO | +--------------------+---------+- 

the engine about which default is written in the support column will be used by default if the engine does not explicitly specify the engine in the create table ... command.

To change the engine (theoretically, not available for any pairs of engines) of an already existing table, use the command:

 > alter table имя_таблицы engine = название_движка;