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select version();
| version() |
|---|
| 10.3.32-MariaDB |
create table `metadata` (`key` varchar(20) primary key, `value` int);
insert into `metadata` values ('logs',null);
create table `logs` (`id` serial);
insert into `logs` () values (),(),(),(),();
begin not atomic
declare `logs_count` int;
select count(*) into `logs_count` from `logs`;
update `metadata` set `value`=`logs_count` where `key`='logs';
end
select * from `metadata`
| key | value |
|---|---|
| logs | 5 |