学习目标

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

准备工作

启动数据库

su - omm
gsql -r

课程作业

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

start transaction;
set local transaction isolation level read committed read only;
show transaction_isolation;
commit;

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

start transaction isolation level read committed read write;
show transaction_isolation;
create table table1(a int);
set local transaction isolation level read committed read only;
show transaction_read_only;
insert into table1 values(1);
rollback;

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

create table table3(a int);
start transaction;
insert into table3 values(1);
savepoint my_savepoint;
insert into table3 values(2);
select * from table3;
rollback to savepoint my_savepoint;
insert into table3 values(3);
commit;
select * from table3;

4. 清理数据

drop table table1;
drop table table3;

课程总结

Day16：学习了openGauss中对于事务控制的操作，能够创建、修改事务，并通过设置savepoint实现相应的回滚操作
Day16 打卡 get√