openGauss 每日一练第 16 天打卡，我来了！又可以学习，真开心~

学习

今天第 16 课，学习openGauss事务控制。

事务是用户定义的一个数据库操作序列，这些操作要么全做要么全不做，是一个不可分割的工作单位！

课后作业打卡

1.以默认方式启动事务1，修改事务隔离级别，查看transaction_isolation

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start transaction;
SET LOCAL TRANSACTION ISOLATION LEVEL READ COMMITTED READ ONLY;
show transaction_isolation;
END;

2.以读写方式启动事务2，创建新表，修改事务为只读事务，查看transaction_read_only，并向表中插入记录

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show transaction_isolation;
START TRANSACTION ISOLATION LEVEL repeatable read READ WRITE;
create table lucifer(id int,name char(20));
SET LOCAL TRANSACTION ISOLATION LEVEL READ COMMITTED READ ONLY;
show transaction_read_only;
insert into lucifer values(1,'Lucifer');
commit;

3.启动事务3，对表进行增删改查，并用到创建savepoint，回滚savepoint和删除savepoint

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START TRANSACTION;
create table lucifer(id int,name char(20));
insert into lucifer values(1,'Lucifer');
select * from lucifer;
SAVEPOINT my_savepoint;
delete from lucifer where id = 1;
ROLLBACK TO SAVEPOINT my_savepoint;
update lucifer set name = 'Lucifer1' where id = 1;
RELEASE SAVEPOINT my_savepoint;
COMMIT;
select * from lucifer;

4.清理数据

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drop table lucifer;

写在最后

今天的作业打卡结束！🎉