| 时间 | +客户端A | +客户端B | +
|---|---|---|
| T1 | ++set session transaction isolation level read uncommitted;start transaction(开启事务); +update account set balance = balance+1000 where id = 1; +select * from account where id = 1; +设置为未提交读，给张三账号+1000，输出为2000 + | ++ + | +
| T2 | ++ + | ++set session transaction isolation level read uncommitted; +start transaction; +select * from account where id = 1; +查询余额输出为2000 + | +
| T3 | ++rollback + | ++ + | +
| T4 | ++ + | ++commit + | +
| T5 | ++ + | ++select * from account where id = 1; +查询余额输出为1000 + | +
| 时间 | +客户端A | +客户端B | +
|---|---|---|
| T1 | ++set session transaction isolation level read uncommitted; +start transaction; +update account set balance = balance-1000 where id = 1; +update account set balance = balance+1000 where id = 2; + | ++ + | +
| T2 | ++ + | ++set session transaction isolation level read uncommitted; +start transaction; +select balance from account where id = 2; +update account set balance = balance -1000 where id = 2; +更新语句被阻塞 + | +
| T3 | ++rollback + | ++ + | +
| T4 | ++ + | ++commit + | +
| 时间 | +客户端A | +客户端B | +
|---|---|---|
| T1 | ++set session transaction isolation level read committed; +start transaction; +select * from account where id = 2; +查询出余额输出为0; + | ++ + | +
| T2 | ++ + | ++set session transaction isolation level read committed; +start transaction; +update account set balance = balance + 1000 where id = 2; +select * from account where id = 2; +commit； +查询余额输出1000 + | +
| T3 | ++select * from account where id = 2; +commit； +查询余额输出1000 + | ++ + | +
| 时间 | +客户端A | +客户端B | +
|---|---|---|
| T1 | ++set session transaction isolation level repeatable read; +start transaction; +select * from account where id = 2; +查询出余额输出为0; + | ++ + | +
| T2 | ++ + | ++set session transaction isolation level repeatable read; +start transaction; +update account set balance = balance + 1000 where id = 2; +select * from account where id = 2; +commit； +查询余额输出1000 + | +
| T3 | ++select * from account where id = 2; +commit； +查询余额输出0 + | ++ + | +
| 时间 | +客户端A | +客户端B | +
|---|---|---|
| T1 | ++set session transaction isolation level repeatable read; +start transaction; +select count(*) from account where id <=10; +输出2; + | ++ + | +
| T2 | ++ + | ++set session transaction isolation level repeatable read; +start transaction; +insert into account(id,name,balance) values(“3”,“王五”,“0”) ; +select count(*) from account where id <=10; +commit； +输出3 + | +
| T3 | ++select count(*) from account where id <=10; +commit； +输出2 + | ++ + | +
| 时间 | +客户端A | +客户端B | +
|---|---|---|
| T1 | ++set session transaction isolation level repeatable read; +start transaction; +select count(*) from account where id =3; +输出0; + | ++ + | +
| T2 | ++ + | ++set session transaction isolation level repeatable read; +start transaction; +insert into account(id,name,balance) values(“3”,“王五”,“0”) ; +commit; + | +
| T3 | ++insert into account(id,name,balance) values(“3”,“王五”,“0”); +主键重复，插入失败 + | ++ + | +
| T4 | ++select count(*) from account where id =3; +输出0; + | ++ + | +
| T5 | ++rollback; + | ++ + | +