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julia2011 · 发表于 2011-12-26 23:17

--可见还是只有一把行锁
--继续
SQL>insert into test select * from test;
insert into test select * from test;

2 rows affected
time used: 56.778(ms) clock tick:30850479. Execute id is 8.
SQL>select * from v$lock where LTYPE='ROW';
select * from v$lock where LTYPE='ROW';
ADDR          TRX_ID       LTYPE          LMODE          BLOCKED
TABLE_ID             ROW_IDX

1    5890464 806    ROW    X    0             1103          0
1 rows got
time used: 55.896(ms) clock tick:16806393. Execute id is 9.

SQL>insert into test select * from test;
insert into test select * from test;

4 rows affected
time used: 1.754(ms) clock tick:2174940. Execute id is 10.
SQL>insert into test select * from test;
insert into test select * from test;

8 rows affected
time used: 1.904(ms) clock tick:2377773. Execute id is 11.
SQL>insert into test select * from test;
insert into test select * from test;

16 rows affected
time used: 1.750(ms) clock tick:2184633. Execute id is 12.
SQL>insert into test select * from test;
insert into test select * from test;

32 rows affected
time used: 1.842(ms) clock tick:2297979. Execute id is 13.
SQL>insert into test select * from test;
insert into test select * from test;

64 rows affected
time used: 1.831(ms) clock tick:2286198. Execute id is 14.
SQL>select * from v$lock where LTYPE='ROW';
select * from v$lock where LTYPE='ROW';
ADDR          TRX_ID       LTYPE          LMODE          BLOCKED
TABLE_ID             ROW_IDX

1    5890464 806    ROW    X    0             1103          0
1 rows got
time used: 1.965(ms) clock tick:2452212. Execute id is 15.
--奇怪，还是一把行锁，不知道多少行算一把锁？

julia2011 · 发表于 2011-12-26 23:19

--客户端B登录：
isql V7.0.1.78-Build(2011.12.09-13870)
SQL>login
server:
user name:
password:
port:
login time used:18.909(ms)
服务器[localhost]:处于普通打开状态
SQL>select * from test;  --查询确实没阻塞也没数据查出来
select * from test;
C1             C2
0 rows got
time used: 95.636(ms) clock tick:35260209. Execute id is 2.
SQL>update test set c1=3;  --想更新，也没数据
update test set c1=3;

0 rows affected
time used: 52.650(ms) clock tick:23052996. Execute id is 20.

客户端A，B都提交后，锁都释放了
SQL>commit;
commit;

time used: 1.290(ms) clock tick:1550484. Execute id is 23.
SQL>select * from v$lock;
select * from v$lock;
ADDR          TRX_ID       LTYPE          LMODE          BLOCKED
TABLE_ID             ROW_IDX
0 rows got
time used: 1.581(ms) clock tick:1972260. Execute id is 28.

----客户端B查询，查到了A提交的所有数据
SQL>select count(*) from test;
select count(*) from test;
COUNT(*)

1    256
1 rows got
time used: 1.474(ms) clock tick:1839231. Execute id is 29.

--客户端A删除数据
SQL>delete from test where c1 =2;
delete from test where c1 =2;

128 rows affected
time used: 72.245(ms) clock tick:38645307. Execute id is 30.

julia2011 · 发表于 2011-12-26 23:21

--客户端A删除数据
SQL>delete from test where c1 =2;
delete from test where c1 =2;

128 rows affected
time used: 72.245(ms) clock tick:38645307. Execute id is 30.
SQL>select * from v$lock;
select * from v$lock;
ADDR          TRX_ID       LTYPE          LMODE          BLOCKED
TABLE_ID             ROW_IDX

1    5890464 807    ROW    V    0             1103          64

2    5890416 807    ROW    V    0             1103          0

3    5890320 807    ROW    v    0             1103          192

4    5890512 807    ROW    V    0             1103          128
4 rows got
time used: 1.614(ms) clock tick:2012508. Execute id is 31.