mariadb/mysql-test/r/lock_multi.result
unknown a49f5cae9a Bug#4118: multi-table UPDATE takes WRITE lock on read table
Ensures that WRITE lock is not obtained on all tables referenced.


mysql-test/r/lock_multi.result:
  Bug#4118
    New test for multi-update locking
mysql-test/r/multi_update.result:
  Bug#4118
    Fix test
mysql-test/t/lock_multi.test:
  Bug#4118
    New test for multi-update locking
mysql-test/t/multi_update.test:
  Bug#4118
    Fix test
sql/sql_parse.cc:
  Bug#4118
    Split multi-update to its own case statement in sql_parse.cc
sql/sql_update.cc:
  Bug#4118
    Overview of locking checking:    
      1. Open and acquire READ lock
      2. Check to see which tables need WRITE lock
      3. Unlock tables and relock
sql/sql_yacc.yy:
  Bug#4118
    Split multi-update to its own case statement in sql_parse.cc
2004-10-03 00:20:47 +01:00

38 lines
772 B
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;
Table 'test.t2' doesn't exist
drop table t1;