mirror of
https://github.com/MariaDB/server.git
synced 2025-01-19 13:32:33 +01:00
d27a15a81c
Addendum fixes after changing the condition variable for the global read lock. The stress test suite revealed some deadlocks. Some were related to the new condition variable (COND_global_read_lock) and some were general problems with the global read lock. It is now necessary to signal COND_global_read_lock whenever COND_refresh is signalled. We need to wait for the release of a global read lock if one is set before every operation that requires a write lock. But we must not wait if we have locked tables by LOCK TABLES. After setting a global read lock a thread waits until all write locks are released.
90 lines
2.5 KiB
Text
90 lines
2.5 KiB
Text
drop table if exists t1,t2;
|
|
create table t1(n int);
|
|
insert into t1 values (1);
|
|
lock tables t1 write;
|
|
update low_priority t1 set n = 4;
|
|
select n from t1;
|
|
unlock tables;
|
|
n
|
|
4
|
|
drop table t1;
|
|
create table t1(n int);
|
|
insert into t1 values (1);
|
|
lock tables t1 read;
|
|
update low_priority t1 set n = 4;
|
|
select n from t1;
|
|
unlock tables;
|
|
n
|
|
1
|
|
drop table t1;
|
|
create table t1 (a int, b int);
|
|
create table t2 (c int, d int);
|
|
insert into t1 values(1,1);
|
|
insert into t1 values(2,2);
|
|
insert into t2 values(1,2);
|
|
lock table t1 read;
|
|
update t1,t2 set c=a where b=d;
|
|
select c from t2;
|
|
c
|
|
2
|
|
drop table t1;
|
|
drop table t2;
|
|
create table t1 (a int);
|
|
create table t2 (a int);
|
|
lock table t1 write, t2 write;
|
|
insert t1 select * from t2;
|
|
drop table t2;
|
|
ERROR 42S02: Table 'test.t2' doesn't exist
|
|
drop table t1;
|
|
create table t1(a int);
|
|
lock tables t1 write;
|
|
show columns from t1;
|
|
Field Type Null Key Default Extra
|
|
a int(11) YES NULL
|
|
unlock tables;
|
|
drop table t1;
|
|
CREATE DATABASE mysqltest_1;
|
|
FLUSH TABLES WITH READ LOCK;
|
|
DROP DATABASE mysqltest_1;
|
|
DROP DATABASE mysqltest_1;
|
|
ERROR HY000: Can't execute the query because you have a conflicting read lock
|
|
UNLOCK TABLES;
|
|
DROP DATABASE mysqltest_1;
|
|
ERROR HY000: Can't drop database 'mysqltest_1'; database doesn't exist
|
|
use mysql;
|
|
LOCK TABLES columns_priv WRITE, db WRITE, host WRITE, user WRITE;
|
|
FLUSH TABLES;
|
|
use mysql;
|
|
SELECT user.Select_priv FROM user, db WHERE user.user = db.user LIMIT 1;
|
|
OPTIMIZE TABLES columns_priv, db, host, user;
|
|
Table Op Msg_type Msg_text
|
|
mysql.columns_priv optimize status OK
|
|
mysql.db optimize status OK
|
|
mysql.host optimize status OK
|
|
mysql.user optimize status OK
|
|
UNLOCK TABLES;
|
|
Select_priv
|
|
N
|
|
use test;
|
|
use test;
|
|
CREATE TABLE t1 (c1 int);
|
|
LOCK TABLE t1 WRITE;
|
|
FLUSH TABLES WITH READ LOCK;
|
|
CREATE TABLE t2 (c1 int);
|
|
UNLOCK TABLES;
|
|
UNLOCK TABLES;
|
|
DROP TABLE t1, t2;
|
|
CREATE TABLE t1 (c1 int);
|
|
LOCK TABLE t1 WRITE;
|
|
FLUSH TABLES WITH READ LOCK;
|
|
CREATE TABLE t2 AS SELECT * FROM t1;
|
|
ERROR HY000: Table 't2' was not locked with LOCK TABLES
|
|
UNLOCK TABLES;
|
|
UNLOCK TABLES;
|
|
DROP TABLE t1;
|
|
create table t1 (f1 int(12) unsigned not null auto_increment, primary key(f1)) engine=innodb;
|
|
lock tables t1 write;
|
|
alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; //
|
|
alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; //
|
|
unlock tables;
|
|
drop table t1;
|