2016-06-29 09:14:22 +02:00
|
|
|
let $MYSQLD_DATADIR= `select @@datadir`;
|
|
|
|
|
|
|
|
|
|
--echo #
|
|
|
|
|
--echo # Test that we can use tables created in MySQL 5.7
|
|
|
|
|
--echo #
|
|
|
|
|
|
|
|
|
|
--copy_file std_data/mysql57_virtual.frm $MYSQLD_DATADIR/test/mysql57_virtual.frm
|
|
|
|
|
--copy_file std_data/mysql57_virtual.MYD $MYSQLD_DATADIR/test/mysql57_virtual.MYD
|
|
|
|
|
--copy_file std_data/mysql57_virtual.MYI $MYSQLD_DATADIR/test/mysql57_virtual.MYI
|
|
|
|
|
|
|
|
|
|
SHOW CREATE TABLE mysql57_virtual;
|
|
|
|
|
insert into mysql57_virtual (a) values (1),(2);
|
|
|
|
|
select * from mysql57_virtual;
|
|
|
|
|
|
|
|
|
|
# We can't do online changes, as the MariaDB storage is incompatible with MySQL
|
2023-06-28 13:37:47 +02:00
|
|
|
--error ER_ALTER_OPERATION_NOT_SUPPORTED
|
MDEV-16329 [5/5] ALTER ONLINE TABLE
* Log rows in online_alter_binlog.
* Table online data is replicated within dedicated binlog file
* Cached data is written on commit.
* Versioning is fully supported.
* Works both wit and without binlog enabled.
* For now savepoints setup is forbidden while ONLINE ALTER goes on.
Extra support is required. We can simply log the SAVEPOINT query events
and replicate them together with row events. But it's not implemented
for now.
* Cache flipping:
We want to care for the possible bottleneck in the online alter binlog
reading/writing in advance.
IO_CACHE does not provide anything better that sequential access,
besides, only a single write is mutex-protected, which is not suitable,
since we should write a transaction atomically.
To solve this, a special layer on top Event_log is implemented.
There are two IO_CACHE files underneath: one for reading, and one for
writing.
Once the read cache is empty, an exclusive lock is acquired (we can wait
for a currently active transaction finish writing), and flip() is emitted,
i.e. the write cache is reopened for read, and the read cache is emptied,
and reopened for writing.
This reminds a buffer flip that happens in accelerated graphics
(DirectX/OpenGL/etc).
Cache_flip_event_log is considered non-blocking for a single reader and a
single writer in this sense, with the only lock held by reader during flip.
An alternative approach by implementing a fair concurrent circular buffer
is described in MDEV-24676.
* Cache managers:
We have two cache sinks: statement and transactional.
It is important that the changes are first cached per-statement and
per-transaction.
If a statement fails, then only statement data is rolled back. The
transaction moves along, however.
Turns out, there's no guarantee that TABLE well persist in
thd->open_tables to the transaction commit moment.
If an error occurs, tables from statement are purged.
Therefore, we can't store te caches in TABLE. Ideally, it should be
handlerton, but we cut the corner and store it in THD in a list.
2020-11-26 12:08:58 +01:00
|
|
|
alter online table mysql57_virtual comment "I am now a MariaDB table", algorithm=nocopy;
|
2016-06-29 09:14:22 +02:00
|
|
|
|
|
|
|
|
alter table mysql57_virtual comment "I am now a MariaDB table";
|
|
|
|
|
SHOW CREATE TABLE mysql57_virtual;
|
|
|
|
|
DROP TABLE mysql57_virtual;
|
|
|
|
|
|
|
|
|
|
--echo #
|
|
|
|
|
--echo # Check MySQL 5.7 syntax
|
|
|
|
|
--echo #
|
|
|
|
|
|
|
|
|
|
create table t1 (a int, b int generated always as (a+1) STORED, c int generated always as (a+2) VIRTUAL);
|
|
|
|
|
show create table t1;
|
|
|
|
|
drop table t1;
|