Oracle 死锁测试

1，建立测试表

create table l (id int);insert into l values(1);insert into l values(2);

2，执行锁测试

需要打开2个会话.

会话1	会话2
select * from l where id=1 for update;
	select * from l where id=2 for update;
select * from l where id=2 for update; ----等待会话2提交。
	select * from l where id=1 for update; ----等待会话1提交。
SQL> select * from l where id=2 for update; select * from l where id=2 for update * ERROR at line 1: ORA-00060: deadlock detected while waiting for resource
//需要执行commit,rollback.会话2才能正常执行。

3，PG锁测试

会话1	会话2
begin;	begin;
select * from l where id=1 for update;
	select * from l where id=2 for update;
select * from l where id=2 for update; #会话等待2
	select * from l where id=1 for update;  #会话2报错，会话rollback; postgres=*# select * from l where id=1 for update; ERROR:  deadlock detected DETAIL:  Process 26109 waits for ShareLock on transaction 585; blocked by process 26104. Process 26104 waits for ShareLock on transaction 586; blocked by process 26109. HINT:  See server log for query details. CONTEXT:  while locking tuple (0,1) in relation "l" postgres=!# select * from l where id=2 for update; ERROR:  current transaction is aborted, commands ignored until end of transaction block postgres=!# select * from l where id=2 for update; ERROR:  current transaction is aborted, commands ignored until end of transaction block postgres=!# commit; ROLLBACK
#会话1正常执行。可以正常commit