database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-30 16:24:05 +03:00
Code Activity

MDEV-16465 Invalid (old?) table or database name or hang in ha_innobase::delete_table and log semaphore wait upon concurrent DDL with foreign keys

Browse Source 
ALTER TABLE locks the table with TL_READ_NO_INSERT, to prevent the
source table modifications while it's being copied. But there's an
indirect way of modifying a table, via cascade FK actions.

After previous commits, an attempt to modify an FK parent table
will cause FK children to be prelocked, so the table-being-altered
cannot be modified by a cascade FK action, because ALTER holds a
lock and prelocking will wait.

But if a new FK is being added by this very ALTER, then the target
table is not locked yet (it's a temporary table). So, we have to
lock FK parents explicitly.
This commit is contained in:
Sergei Golubchik
2018-07-19 01:03:14 +02:00
parent e81f101dac
commit 9180e8666b
6 changed files with 132 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

36
mysql-test/suite/innodb/r/foreign-keys.result
View File

@ -51,3 +51,39 @@ c d
6 30
drop table t2, t1;
drop user foo;
create table t1 (f1 int primary key) engine=innodb;
create table t2 (f2 int primary key) engine=innodb;
create table t3 (f3 int primary key, foreign key (f3) references t2(f2)) engine=innodb;
insert into t1 values (1),(2),(3),(4),(5);
insert into t2 values (1),(2),(3),(4),(5);
insert into t3 values (1),(2),(3),(4),(5);
connect con1,localhost,root;
set debug_sync='alter_table_before_rename_result_table signal g1 wait_for g2';
alter table t2 add constraint foreign key (f2) references t1(f1) on delete cascade on update cascade;
connection default;
set debug_sync='before_execute_sql_command wait_for g1';
update t1 set f1 = f1 + 100000 limit 2;
connect con2,localhost,root;
kill query UPDATE;
disconnect con2;
connection default;
ERROR 70100: Query execution was interrupted
set debug_sync='now signal g2';
connection con1;
show create table t2;
Table Create Table
t2 CREATE TABLE `t2` (
`f2` int(11) NOT NULL,
PRIMARY KEY (`f2`),
CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`f2`) REFERENCES `t1` (`f1`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=latin1
disconnect con1;
connection default;
select * from t2 where f2 not in (select f1 from t1);
f2
select * from t3 where f3 not in (select f2 from t2);
f3
drop table t3;
drop table t2;
drop table t1;
set debug_sync='reset';