T2 T1 |
S |
X |
RS |
RX |
SRX |
- |
S |
Y |
N |
Y |
N |
N |
Y |
X |
N |
N |
N |
N |
N |
Y |
RS |
Y |
N |
Y |
Y |
Y |
Y |
RX |
N |
N |
Y |
Y |
N |
Y |
SRX |
N |
N |
Y |
N |
N |
Y |
- |
Y |
Y |
Y |
Y |
Y |
Y |
表一:Oracle数据库TM锁的相容矩阵
SQL语句 |
表锁模式 |
允许的锁模式 |
Select * from table_name…… |
无 |
RS、RX、S、SRX、X |
Insert into table_name…… |
RX |
RS、RX |
Update table_name…… |
RX |
RS、RX |
Delete from table_name…… |
RX |
RS、RX |
Select * from table_name for update |
RS |
RS、RX、S、SRX |
lock table table_name in row share mode |
RS |
RS、RX、S、SRX |
lock table table_name in row exclusive mode |
RX |
RS、RX |
lock table table_name in share mode |
S |
RS、S |
lock table table_name in share row exclusive mode |
SRX |
RS |
lock table table_name in exclusive mode |
X |
无 |
表二:Oracle数据库TM锁小结