1. Frédéric Descamps
Community Manager
MySQL
August 2022
MySQL User Group NL
MySQL 8.0 - Overview of the last 18 months

2. Who am I ?
about.me/lefred
Copyright @ 2022 Oracle and/or its affiliates.
2

3. Frédéric Descamps
@lefred
MySQL Evangelist
Managing MySQL since 3.20
devops believer
living in Belgium
h ps://lefred.be
Copyright @ 2022 Oracle and/or its affiliates.
3

4. 18 months of development
from MySQL 8.0.23 to 8.0.30
Copyright @ 2022 Oracle and/or its affiliates.
4

5. what's new from January 2021 ?
There are plenty of cool stu pre-8.0.23 that you may know, like...
Copyright @ 2022 Oracle and/or its affiliates.
5

6. Hash Joins
New InnoDB Doublewrie Bu er
Error Log in a table
Binary Log compression
what's new from January 2021 ?
There are plenty of cool stu pre-8.0.23 that you may know, like...
Copyright @ 2022 Oracle and/or its affiliates.
5

7. Hash Joins
New InnoDB Doublewrie Bu er
Error Log in a table
Binary Log compression
what's new from January 2021 ?
There are plenty of cool stu pre-8.0.23 that you may know, like...
But also other things you might not have heard about, like ...
Copyright @ 2022 Oracle and/or its affiliates.
5

8. Hash Joins
New InnoDB Doublewrie Bu er
Error Log in a table
Binary Log compression
Runtime disabling InnoDB Redo Log
Per-user Comments & A ributes
MySQL Document Store JSON validation
TVC Support
Account Management Support
Automatic Async Replication connection
Failover
what's new from January 2021 ?
There are plenty of cool stu pre-8.0.23 that you may know, like...
But also other things you might not have heard about, like ...
Copyright @ 2022 Oracle and/or its affiliates.
5

9. pre-8.0.23 examples
Runtime disabling InnoDB Redo Log
MySQL > ALTER INSTANCE DISABLE INNODB REDO_LOG;
MySQL > SELECT * FROM performance_schema.global_status
WHERE VARIABLE_NAME='Innodb_redo_log_enabled';
+-------------------------+----------------+
| VARIABLE_NAME | VARIABLE_VALUE |
+-------------------------+----------------+
| Innodb_redo_log_enabled | OFF |
+-------------------------+----------------+
Copyright @ 2022 Oracle and/or its affiliates.
6

10. pre-8.0.23 examples
Runtime disabling InnoDB Redo Log
MySQL > ALTER INSTANCE DISABLE INNODB REDO_LOG;
MySQL > SELECT * FROM performance_schema.global_status
WHERE VARIABLE_NAME='Innodb_redo_log_enabled';
+-------------------------+----------------+
| VARIABLE_NAME | VARIABLE_VALUE |
+-------------------------+----------------+
| Innodb_redo_log_enabled | OFF |
+-------------------------+----------------+
Per-user Comments & A ributes
MySQL > ALTER USER fred ATTRIBUTE '{"country": "belgium", "OS": "Linux"}';
MySQL > SELECT *, attribute->>"$.country" country
FROM INFORMATION_SCHEMA.USER_ATTRIBUTES WHERE USER='fred';
+------+------+---------------------------------------+---------+
| USER | HOST | ATTRIBUTE | country |
+------+------+---------------------------------------+---------+
| fred | % | {"OS": "Linux", "country": "belgium"} | belgium |
+------+------+---------------------------------------+---------+
Copyright @ 2022 Oracle and/or its affiliates.
6

11. pre-8.0.23 examples (2)
MySQL Document Store JSON validation
Copyright @ 2022 Oracle and/or its affiliates.
7

12. MySQL > TABLE t;
+----+--------+------+
| id | date | num |
+----+--------+------+
| 1 | 202201 | 3363 |
| 2 | 202202 | 5363 |
| 3 | 202203 | 4344 |
| 4 | 202204 | 1404 |
| 5 | 202205 | 2300 |
+----+--------+------+
5 rows in set (0.0079 sec)
MySQL > INSERT INTO t VALUES
ROW(0, 202206, 3100),
ROW(0, 202207, 2456);
MySQL > TABLE t LIMIT 2 OFFSET 5;
+----+--------+------+
| id | date | num |
+----+--------+------+
| 6 | 202206 | 3100 |
| 7 | 202207 | 2456 |
+----+--------+------+
pre-8.0.23 examples (3)
TVC Support
Support explicit tables clauses and table value constructors according the SQL standard:
Copyright @ 2022 Oracle and/or its affiliates.
8

13. pre-8.0.23 examples (4)
Account Management Enhancements
Too many consecutive login failures due to incorrect passwords can cause temporary
account locking
MySQL > CREATE USER 'usergroupnl'@'localhost'
IDENTIFIED BY 'WeOranj3&'
FAILED_LOGIN_ATTEMPTS 1 PASSWORD_LOCK_TIME 1;
Copyright @ 2022 Oracle and/or its affiliates.
9

14. MySQL 8.0.23 and beyond
now the new stu !
Copyright @ 2022 Oracle and/or its affiliates.
10

15. Replication
rst a word about something that was particularly close to our hearts
Copyright @ 2022 Oracle and/or its affiliates.
11

16. Replication
rst a word about something that was particularly close to our hearts
We kept the long task of removing o ensive words in our code (commands, tables, ...)
Now:
mysql> CHANGE REPLICATION SOURCE TO
-> SOURCE_HOST='source_host_name',
-> SOURCE_USER='replication_user_name',
-> SOURCE_PASSWORD='replication_password',
-> SOURCE_LOG_FILE='recorded_log_file_name',
-> SOURCE_LOG_POS=recorded_log_position;
Copyright @ 2022 Oracle and/or its affiliates.
11

17. Replication & Group Replication
replication from non GTID enabled replica (8.0.23)
automatic connection failover for async replication for Group Replication (8.0.23)
alternative UUID for Group Replication's generated transactions for view changes
(8.0.26)
multi-threaded replication enabled by default (8.0.27)
Group Communication engine (GCS) can now use a single leader when using single-
primary mode to improve performance
Copyright @ 2022 Oracle and/or its affiliates.
12

18. Replication & Group Replication
Asynchronous Replication Channel automatically follows the Primary (8.0.27)
support of native MySQL Server's connection security for Group Replication (8.0.27)
it's possible to enable Paxos single leader for Group Replication (8.0.27)
new system variable to control automatic purging of binary logs:
binlog_expire_logs_auto_purge (8.0.29)
Group Replication memory usage is now instrumented in Performance_Schema
(8.0.30)
Copyright @ 2022 Oracle and/or its affiliates.
13

19. InnoDB
indexes can now be built simultaneously instead of serially: innodb_ddl_threads)
(8.0.27)
see h ps://lefred.be/content/mysql-8-0-innodb-parallel-threads-for-online-ddl-
operations/
Clone now permits concurrent DDL operations on the donor (8.0.27)
InnoDB now supports the following operation using ALGORITHM=INSTANT:
ALTER TABLE ... RENAME COLUMN (8.0.28)
ALTER TABLE ... DROP COLUMN (8.0.29)
Copyright @ 2022 Oracle and/or its affiliates.
14

20. InnoDB (2)
innodb_open_ les can be set at runtime (8.0.28)
two new values for the innodb_doublewrite system variable (8.0.30):
DETECT_ONLY
DETECT_AND_RECOVER
new Redo Log architecture (8.0.30)
Copyright @ 2022 Oracle and/or its affiliates.
15

21. InnoDB New Redo Log architecture
The redo log is a write ahead log of changes applied to contents of data pages.
It provides durability for all changes applied to the pages. (The 'D' in ACID)
In case of crash, it is used to recover modi cations to pages that were modi ed but have
not been ushed to disk.
Copyright @ 2022 Oracle and/or its affiliates.
16

22. InnoDB New Redo Log architecture
Since MySQL 8.0.30 it's possible to dynamically resize the InnoDB redo logs.
Overview of the changes:
redo logs are now on a dedicated directory: #innodb_redo
32 les (innodb_redo_log_capacity / 32)
the les are re-used but renamed, rst as #ib_redoXX_tmp when not in use and where
XX is a new incremented number
innodb_log_ les_in_group and innodb_log_ le_size are now deprecated
and ignored
Copyright @ 2022 Oracle and/or its affiliates.
17

23. InnoDB New Redo Log architecture
Redo log les use an #ib_redoN naming convention, where N is the redo log le number.
Spare redo log les are denoted by a _tmp su x:
[root@dell mysql]# ls #innodb_redo/
'#ib_redo146' '#ib_redo152_tmp' '#ib_redo158_tmp' '#ib_redo164_tmp' '#ib_redo170_tmp' '#ib_redo176_tmp'
'#ib_redo147' '#ib_redo153_tmp' '#ib_redo159_tmp' '#ib_redo165_tmp' '#ib_redo171_tmp' '#ib_redo177_tmp'
'#ib_redo148' '#ib_redo154_tmp' '#ib_redo160_tmp' '#ib_redo166_tmp' '#ib_redo172_tmp'
'#ib_redo149_tmp' '#ib_redo155_tmp' '#ib_redo161_tmp' '#ib_redo167_tmp' '#ib_redo173_tmp'
'#ib_redo150_tmp' '#ib_redo156_tmp' '#ib_redo162_tmp' '#ib_redo168_tmp' '#ib_redo174_tmp'
'#ib_redo151_tmp' '#ib_redo157_tmp' '#ib_redo163_tmp' '#ib_redo169_tmp' '#ib_redo175_tmp'
Each ordinary redo log le is associated with a particular range of LSN values:
MySQL > SELECT FILE_ID, START_LSN, END_LSN, format_bytes(SIZE_IN_BYTES) SIZE_IN_MB,
IS_FULL, CONSUMER_LEVEL FROM performance_schema.innodb_redo_log_files;
+---------+-----------+-----------+------------+---------+----------------+
| FILE_ID | START_LSN | END_LSN | SIZE_IN_MB | IS_FULL | CONSUMER_LEVEL |
+---------+-----------+-----------+------------+---------+----------------+
| 146 | 478121984 | 498501632 | 19.44 MiB | 1 | 0 |
| 147 | 498501632 | 518881280 | 19.44 MiB | 1 | 0 |
| 148 | 518881280 | 539260928 | 19.44 MiB | 0 | 0 |
+---------+-----------+-----------+------------+---------+----------------+
Copyright @ 2022 Oracle and/or its affiliates.
18

24. InnoDB New Redo Log architecture
Calculating the optimal size
During peak tra c time, you can get an estimation of the required amount for the Redo Log
Size by running this query:
MySQL > SELECT VARIABLE_VALUE FROM performance_schema.global_status
WHERE VARIABLE_NAME='Innodb_redo_log_current_lsn'
INTO @a; SELECT SLEEP(60) INTO @garb; SELECT VARIABLE_VALUE
FROM performance_schema.global_status
WHERE VARIABLE_NAME='Innodb_redo_log_current_lsn'
INTO @b; SELECT ROUND(ABS(@a - @b)/1024/1024,2) AS MB_per_min,
ROUND(ABS(@a - @b)/1024/1024*60,2) AS MB_per_hour;
+------------+-------------+
| MB_per_min | MB_per_hour |
+------------+-------------+
| 10.37 | 622 |
+------------+-------------+
Copyright @ 2022 Oracle and/or its affiliates.
19

25. InnoDB New Redo Log architecture
Calculating the optimal size (2)
The rule of thumb is to make the Redo Logs big enough to hold at most 1h of logs:
MySQL > SELECT format_bytes(@@innodb_redo_log_capacity);
+------------------------------------------+
| format_bytes(@@innodb_redo_log_capacity) |
+------------------------------------------+
| 100.00 MiB |
+------------------------------------------+
MySQL > SET GLOBAL innodb_redo_log_capacity=622*1024*1024;
MySQL > SELECT format_bytes(@@innodb_redo_log_capacity);
+------------------------------------------+
| format_bytes(@@innodb_redo_log_capacity) |
+------------------------------------------+
| 622.00 MiB |
+------------------------------------------+
Copyright @ 2022 Oracle and/or its affiliates.
20

26. InnoDB Primary Keys, Invisible column and GIPK
For InnoDB, a Primary Key is required and a good one is even be er !
Copyright @ 2022 Oracle and/or its affiliates.
21

27. InnoDB Primary Keys, Invisible column and GIPK
For InnoDB, a Primary Key is required and a good one is even be er !
Some theory
InnoDB stores data in table spaces. The records are stored and sorted using the clustered
index (PK).
Copyright @ 2022 Oracle and/or its affiliates.
21

28. InnoDB Primary Keys, Invisible column and GIPK
For InnoDB, a Primary Key is required and a good one is even be er !
Some theory
InnoDB stores data in table spaces. The records are stored and sorted using the clustered
index (PK).
All secondary indexes also contain the primary key as the right-most column in the index
(even if this is not exposed). That means when a secondary index is used to retrieve a
record, two indexes are used: rst the secondary one pointing to the primary key that will be
used to nally retrieve the record.
Copyright @ 2022 Oracle and/or its affiliates.
21

29. InnoDB Primary Key (2)
So, the primary key impact how the values are inserted and the size of the secondary
indexes. A non sequential PK can lead to many random IOPS.
Copyright @ 2022 Oracle and/or its affiliates.
22

30. Also, it's more and more common to use
application that generates complete
random primary keys...that means if the
Primary Key is not sequential, InnoDB will
have to heavily re-balance all the pages on
inserts.
InnoDB Primary Key (2)
So, the primary key impact how the values are inserted and the size of the secondary
indexes. A non sequential PK can lead to many random IOPS.
Copyright @ 2022 Oracle and/or its affiliates.
22

31. InnoDB Primary Key (3)
If we compare the same load (inserts) when using an auto_increment integer as Primary
Key, we can see that only the latest pages are recently touched:
Generated with h ps://github.com/jeremycole/innodb_ruby from @jeremycole
Copyright @ 2022 Oracle and/or its affiliates.
23

32. InnoDB Primary Key ? No Key !
Another common mistake when using InnoDB is to not de ne any Primary Key.
Copyright @ 2022 Oracle and/or its affiliates.
24

33. InnoDB Primary Key ? No Key !
Another common mistake when using InnoDB is to not de ne any Primary Key.
When no primary key is de ned, the rst unique not null key is used. And if none is
available, InnoDB will create an hidden primary key (6 bytes).
Copyright @ 2022 Oracle and/or its affiliates.
24

34. InnoDB Primary Key ? No Key !
Another common mistake when using InnoDB is to not de ne any Primary Key.
When no primary key is de ned, the rst unique not null key is used. And if none is
available, InnoDB will create an hidden primary key (6 bytes).
The problem with such key is that you don’t have any control on it and worse, this value is
global to all tables without primary keys and can be a contention problem if you perform
multiple simultaneous writes on such tables (dict_sys->mutex).
Copyright @ 2022 Oracle and/or its affiliates.
24

35. InnoDB Primary Key ? No Key !
Another common mistake when using InnoDB is to not de ne any Primary Key.
When no primary key is de ned, the rst unique not null key is used. And if none is
available, InnoDB will create an hidden primary key (6 bytes).
The problem with such key is that you don’t have any control on it and worse, this value is
global to all tables without primary keys and can be a contention problem if you perform
multiple simultaneous writes on such tables (dict_sys->mutex).
And if you plan for High Availability, tables without Primary Key are not supported !
Copyright @ 2022 Oracle and/or its affiliates.
24

36. InnoDB Primary Key ? No Key ! (2)
Luckily since MySQL 8.0.23 there is a solution: Invisible Column !
Copyright @ 2022 Oracle and/or its affiliates.
25

37. InnoDB Primary Key ? No Key ! (2)
Luckily since MySQL 8.0.23 there is a solution: Invisible Column !
You can now add an invisible auto_increment Primary Key to a table not having any
Primary Key !
Copyright @ 2022 Oracle and/or its affiliates.
25

38. InnoDB Primary Key ? No Key ! (2)
To identify those tables, run the following SQL statement:
SELECT tables.table_schema , tables.table_name , tables.engine
FROM information_schema.tables LEFT JOIN (
SELECT table_schema , table_name
FROM information_schema.statistics
GROUP BY table_schema, table_name, index_name
HAVING SUM(
CASE WHEN non_unique = 0
AND nullable != 'YES' then 1 else 0 end ) = count(*) ) puks
ON tables.table_schema = puks.table_schema
AND tables.table_name = puks.table_name
WHERE puks.table_name IS null
AND tables.table_type = 'BASE TABLE'
AND Engine="InnoDB";
Copyright @ 2022 Oracle and/or its affiliates.
26

39. InnoDB Primary Key ? No Key ! (2)
To identify those tables, run the following SQL statement:
SELECT tables.table_schema , tables.table_name , tables.engine
FROM information_schema.tables LEFT JOIN (
SELECT table_schema , table_name
FROM information_schema.statistics
GROUP BY table_schema, table_name, index_name
HAVING SUM(
CASE WHEN non_unique = 0
AND nullable != 'YES' then 1 else 0 end ) = count(*) ) puks
ON tables.table_schema = puks.table_schema
AND tables.table_name = puks.table_name
WHERE puks.table_name IS null
AND tables.table_type = 'BASE TABLE'
AND Engine="InnoDB";
Copyright @ 2022 Oracle and/or its affiliates.
+--------------+-----------------+--------+
| TABLE_SCHEMA | TABLE_NAME | ENGINE |
+--------------+-----------------+--------+
| slack | some_table | InnoDB |
| test | default_test | InnoDB |
| test | t1 | InnoDB |
| world | orders | InnoDB |
| world | sales | InnoDB |
| dbt3 | time_statistics | InnoDB |
+--------------+-----------------+--------+
26

40. InnoDB Primary Key ? No Key ! (3)
Another nice query to identify the tables using an hidden clustered index is to lookup for
GEN_CLUST_INDEX like this:
SELECT i.TABLE_ID,
t.NAME
FROM INFORMATION_SCHEMA.INNODB_INDEXES i
JOIN
INFORMATION_SCHEMA.INNODB_TABLES t ON (i.TABLE_ID = t.TABLE_ID)
WHERE
i.NAME='GEN_CLUST_INDEX';
see h ps://elephantdolphin.blogspot.com/2021/08/ nding-your-hidden-innodb-primary.html
Copyright @ 2022 Oracle and/or its affiliates.
27

41. InnoDB Primary Key ? No Key ! (3)
Another nice query to identify the tables using an hidden clustered index is to lookup for
GEN_CLUST_INDEX like this:
SELECT i.TABLE_ID,
t.NAME
FROM INFORMATION_SCHEMA.INNODB_INDEXES i
JOIN
INFORMATION_SCHEMA.INNODB_TABLES t ON (i.TABLE_ID = t.TABLE_ID)
WHERE
i.NAME='GEN_CLUST_INDEX';
see h ps://elephantdolphin.blogspot.com/2021/08/ nding-your-hidden-innodb-primary.html
Copyright @ 2022 Oracle and/or its affiliates.
+----------+----------------------+
| TABLE_ID | NAME |
+----------+----------------------+
| 1198 | slack/some_table |
| 1472 | test/default_test |
| 1492 | test/t1 |
| 2018 | world/orders |
| 2019 | world/sales |
| 2459 | dbt3/time_statistics |
+----------+----------------------+
27

42. InnoDB Primary Key ? No Key ! (4)
Copyright @ 2022 Oracle and/or its affiliates.
28

43. InnoDB Primary Key ? No Key ! (4)
Perfect for replication !
Copyright @ 2022 Oracle and/or its affiliates.
28

44. InnoDB Primary Key ? No Key ! (5)
Copyright @ 2022 Oracle and/or its affiliates.
29

45. InnoDB GIPK mode
Since MySQL 8.0.30, MySQL supports generated invisible primary keys when running in
GIPK mode !
GIPK mode is controlled by the sql_generate_invisible_primary_key server
system variable.
Copyright @ 2022 Oracle and/or its affiliates.
30

46. InnoDB GIPK mode
Since MySQL 8.0.30, MySQL supports generated invisible primary keys when running in
GIPK mode !
GIPK mode is controlled by the sql_generate_invisible_primary_key server
system variable.
When MySQL is running in GIPK mode, a primary key is added to a table by the server, the
column and key name is always my_row_id.
Copyright @ 2022 Oracle and/or its affiliates.
30

47. InnoDB GIPK mode - example
MySQL > SELECT @@sql_generate_invisible_primary_key;
+--------------------------------------+
| @@sql_generate_invisible_primary_key |
+--------------------------------------+
| 1 |
+--------------------------------------+
MySQL > CREATE TABLE usergroupnl (name varchar(20), beers int unsigned);
MySQL > INSERT INTO usergroupnl VALUES ('Carsten', 0), ('lefred',1);
Query OK, 2 rows affected (0.0073 sec)
MySQL > SELECT * FROM usergroupnl;
+---------+-------+
| name | beers |
+---------+-------+
| Carsten | 0 |
| lefred | 1 |
+---------+-------+
2 rows in set (0.0002 sec)
Copyright @ 2022 Oracle and/or its affiliates.
31

48. InnoDB GIPK mode - example (2)
MySQL > SHOW CREATE TABLE usergroupnlG
*************************** 1. row ***************************
Table: usergroupnl
Create Table: CREATE TABLE `usergroupnl` (
`my_row_id` bigint unsigned NOT NULL AUTO_INCREMENT /*!80023 INVISIBLE */,
`name` varchar(20) DEFAULT NULL,
`beers` int unsigned DEFAULT NULL,
PRIMARY KEY (`my_row_id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
Copyright @ 2022 Oracle and/or its affiliates.
32

49. InnoDB GIPK mode - example (2)
MySQL > SHOW CREATE TABLE usergroupnlG
*************************** 1. row ***************************
Table: usergroupnl
Create Table: CREATE TABLE `usergroupnl` (
`my_row_id` bigint unsigned NOT NULL AUTO_INCREMENT /*!80023 INVISIBLE */,
`name` varchar(20) DEFAULT NULL,
`beers` int unsigned DEFAULT NULL,
PRIMARY KEY (`my_row_id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
MySQL > SELECT *, my_row_id FROM usergroupnl;
+---------+-------+-----------+
| name | beers | my_row_id |
+---------+-------+-----------+
| Carsten | 0 | 1 |
| lefred | 1 | 2 |
+---------+-------+-----------+
2 rows in set (0.0003 sec)
Copyright @ 2022 Oracle and/or its affiliates.
32

50. InnoDB GIPK mode - example (3)
It's also possible to hide it completely (for some legacy application that could rely on
informantion_schema and SHOW CREATE TABLE):
MySQL > SET show_gipk_in_create_table_and_information_schema = 0;
MySQL > SHOW CREATE TABLE usergroupnlG
*************************** 1. row ***************************
Table: usergroupnl
Create Table: CREATE TABLE `usergroupnl` (
`name` varchar(20) DEFAULT NULL,
`beers` int unsigned DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
Copyright @ 2022 Oracle and/or its affiliates.
33

51. InnoDB GIPK mode - example (4)
MySQL > SELECT COLUMN_NAME, ORDINAL_POSITION, DATA_TYPE, COLUMN_KEY
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = "usergroupnl";
+-------------+------------------+-----------+------------+
| COLUMN_NAME | ORDINAL_POSITION | DATA_TYPE | COLUMN_KEY |
+-------------+------------------+-----------+------------+
| beers | 3 | int | |
| name | 2 | varchar | |
+-------------+------------------+-----------+------------+
MySQL > SET show_gipk_in_create_table_and_information_schema = 1;
MySQL > SELECT COLUMN_NAME, ORDINAL_POSITION, DATA_TYPE, COLUMN_KEY
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = "usergroupnl";
+-------------+------------------+-----------+------------+
| COLUMN_NAME | ORDINAL_POSITION | DATA_TYPE | COLUMN_KEY |
+-------------+------------------+-----------+------------+
| beers | 3 | int | |
| my_row_id | 1 | bigint | PRI |
| name | 2 | varchar | |
+-------------+------------------+-----------+------------+
Copyright @ 2022 Oracle and/or its affiliates.
34

52. . generally they are completely radom
and cause clustered index re-banlancing
. they are included in each secondary
indexes (consuming disk and memory)
InnoDB Primary Key - What about UUID ?
There are 2 main problems with UUID's as Primary Key:
Copyright @ 2022 Oracle and/or its affiliates.
35

53. InnoDB Primary Key - What about UUID ? (2)
Example:
MySQL > CREATE TABLE usergroupnl3 (
uuid VARCHAR(36) DEFAULT (UUID()) PRIMARY KEY,
name VARCHAR(20), beers int unsigned);
MySQL > SELECT * FROM usergroupnl3;
+--------------------------------------+---------+-------+
| uuid | name | beers |
+--------------------------------------+---------+-------+
| 17cd1188-1fa0-11ed-ba36-c8cb9e32df8e | Carsten | 0 |
| 17cd12e2-1fa0-11ed-ba36-c8cb9e32df8e | lefred | 1 |
| 478368a0-1fa0-11ed-ba36-c8cb9e32df8e | Lev | 0 |
| 47836a77-1fa0-11ed-ba36-c8cb9e32df8e | Zouhair | 1 |
+--------------------------------------+---------+-------+
Copyright @ 2022 Oracle and/or its affiliates.
36

54. InnoDB Primary Key - What about UUID ? (3)
Let's insert 2 new records:
MySQL > INSERT INTO usergroupnl3 (name, beers) VALUES ("Rob",1), ("Ron",5);
Query OK, 2 rows affected (0.0069 sec)
Copyright @ 2022 Oracle and/or its affiliates.
37

55. InnoDB Primary Key - What about UUID ? (3)
Let's insert 2 new records:
MySQL > INSERT INTO usergroupnl3 (name, beers) VALUES ("Rob",1), ("Ron",5);
Query OK, 2 rows affected (0.0069 sec)
MySQL > SELECT * FROM usergroupnl3;
+--------------------------------------+---------+-------+
| uuid | name | beers |
+--------------------------------------+---------+-------+
| 17cd1188-1fa0-11ed-ba36-c8cb9e32df8e | Carsten | 0 |
| 17cd12e2-1fa0-11ed-ba36-c8cb9e32df8e | lefred | 1 |
| 36f1ce9a-1fa1-11ed-ba36-c8cb9e32df8e | Rob | 1 |
| 36f1d158-1fa1-11ed-ba36-c8cb9e32df8e | Ron | 5 |
| 478368a0-1fa0-11ed-ba36-c8cb9e32df8e | Lev | 0 |
| 47836a77-1fa0-11ed-ba36-c8cb9e32df8e | Zouhair | 1 |
+--------------------------------------+---------+-------+
Copyright @ 2022 Oracle and/or its affiliates.
37

56. InnoDB Primary Key - What about UUID ? (4)
OUPS ! We have rebalanced the clustered index !
What does that mean again ??
Copyright @ 2022 Oracle and/or its affiliates.
38

57. InnoDB Primary Key - What about UUID ? (4)
OUPS ! We have rebalanced the clustered index !
What does that mean again ??
Let me try to explain this with this high level and simpli ed example:
Copyright @ 2022 Oracle and/or its affiliates.
38

58. Let's imagine one InnoDB Page can store 4
records (this is just a ction), and we have
inserted some records using a random
Primary Key:
InnoDB Primary Key - What about UUID ? (5)
OUPS ! We have rebalanced the clustered index !
Copyright @ 2022 Oracle and/or its affiliates.
39

59. Let's imagine one InnoDB Page can store 4
records (this is just a ction), and we have
inserted some records using a random
Primary Key:
And now we insert a new record and the
Primary Key is AA:
All pages were modi ed to <rebalance= the
clustered index ! Imagine if this was a 4TB
table !!
InnoDB Primary Key - What about UUID ? (5)
OUPS ! We have rebalanced the clustered index !
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39

60. InnoDB Primary Key - What about UUID ? (6)
And just for info, each entry in the Primary Key Index take 146 bytes(*):
MySQL > EXPLAIN SELECT * FROM usergroupnl3 WHERE
uuid='36f1d158-1fa1-11ed-ba36-c8cb9e32df8e'G
*************************** 1. row ***************************
id: 1
select_type: SIMPLE
table: usergroupnl3
partitions: NULL
type: const
possible_keys: PRIMARY
key: PRIMARY
key_len: 146
ref: const
rows: 1
filtered: 100
Extra: NULL
(*) worse case when using characters using 4 bytes each (uft8mb4)
Copyright @ 2022 Oracle and/or its affiliates.
40

61. InnoDB Primary Key - What about UUID ? (7)
Recommended solution
. use a smaller datatype: BINARTY(16)
. store the UUID sequentially: UUID_TO_BIN(..., swap_ ag)
The time-low and time-high parts (the rst and third groups of hexadecimal digits,
respectively) are swapped.
Copyright @ 2022 Oracle and/or its affiliates.
41

62. InnoDB Primary Key - What about UUID ? (8)
Recommended solution - example
MySQL > CREATE TABLE usergroupnl2 (
uuid BINARY(16) DEFAULT (UUID_TO_BIN(UUID(), 1)) PRIMARY KEY,
name VARCHAR(20), beers int unsigned);
MySQL > SELECT * FROM usergroupnl2;
+------------------------------------+---------+-------+
| uuid | name | beers |
+------------------------------------+---------+-------+
| 0x11ED1F9F633ECB6CBA36C8CB9E32DF8E | Carsten | 0 |
| 0x11ED1F9F633ECD6FBA36C8CB9E32DF8E | lefred | 1 |
+------------------------------------+---------+-------+
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42

63. InnoDB Primary Key - What about UUID ? (8)
Recommended solution - example
MySQL > CREATE TABLE usergroupnl2 (
uuid BINARY(16) DEFAULT (UUID_TO_BIN(UUID(), 1)) PRIMARY KEY,
name VARCHAR(20), beers int unsigned);
MySQL > SELECT * FROM usergroupnl2;
+------------------------------------+---------+-------+
| uuid | name | beers |
+------------------------------------+---------+-------+
| 0x11ED1F9F633ECB6CBA36C8CB9E32DF8E | Carsten | 0 |
| 0x11ED1F9F633ECD6FBA36C8CB9E32DF8E | lefred | 1 |
+------------------------------------+---------+-------+
MySQL > SELECT BIN_TO_UUID(uuid,1), name, beers FROM usergroupnl2;
+--------------------------------------+---------+-------+
| BIN_TO_UUID(uuid,1) | name | beers |
+--------------------------------------+---------+-------+
| 633ecb6c-1f9f-11ed-ba36-c8cb9e32df8e | Carsten | 0 |
| 633ecd6f-1f9f-11ed-ba36-c8cb9e32df8e | lefred | 1 |
+--------------------------------------+---------+-------+
Copyright @ 2022 Oracle and/or its affiliates.
42

64. InnoDB Primary Key - What about UUID ? (9)
Recommended solution - example
MySQL > INSERT INTO usergroupnl2 (name, beers) VALUES ("Rob",1), ("Ron",5);
MySQL > SELECT * FROM usergroupnl2;
+------------------------------------+---------+-------+
| uuid | name | beers |
+------------------------------------+---------+-------+
| 0x11ED1F9F633ECB6CBA36C8CB9E32DF8E | Carsten | 0 |
| 0x11ED1F9F633ECD6FBA36C8CB9E32DF8E | lefred | 1 |
| 0x11ED1FA537C57361BA36C8CB9E32DF8E | Rob | 1 |
| 0x11ED1FA537C5752DBA36C8CB9E32DF8E | Ron | 5 |
+------------------------------------+---------+-------+
Copyright @ 2022 Oracle and/or its affiliates.
43

65. InnoDB Primary Key - What about UUID ? (9)
Recommended solution - example
MySQL > INSERT INTO usergroupnl2 (name, beers) VALUES ("Rob",1), ("Ron",5);
MySQL > SELECT * FROM usergroupnl2;
+------------------------------------+---------+-------+
| uuid | name | beers |
+------------------------------------+---------+-------+
| 0x11ED1F9F633ECB6CBA36C8CB9E32DF8E | Carsten | 0 |
| 0x11ED1F9F633ECD6FBA36C8CB9E32DF8E | lefred | 1 |
| 0x11ED1FA537C57361BA36C8CB9E32DF8E | Rob | 1 |
| 0x11ED1FA537C5752DBA36C8CB9E32DF8E | Ron | 5 |
+------------------------------------+---------+-------+
MySQL > SELECT BIN_TO_UUID(uuid,1), name, beers FROM usergroupnl2;
+--------------------------------------+---------+-------+
| BIN_TO_UUID(uuid,1) | name | beers |
+--------------------------------------+---------+-------+
| 633ecb6c-1f9f-11ed-ba36-c8cb9e32df8e | Carsten | 0 |
| 633ecd6f-1f9f-11ed-ba36-c8cb9e32df8e | lefred | 1 |
| 37c57361-1fa5-11ed-ba36-c8cb9e32df8e | Rob | 1 |
| 37c5752d-1fa5-11ed-ba36-c8cb9e32df8e | Ron | 5 |
+--------------------------------------+---------+-------+
Copyright @ 2022 Oracle and/or its affiliates.
43

66. InnoDB Primary Key - What about UUID ? (10)
Recommended solution - example
Take a look at the size of each entry in the INDEX (and same amount added to each secondary index)
MySQL > EXPLAIN SELECT * FROM usergroupnl2
WHERE uuid=UUID_TO_BIN("37c5752d-1fa5-11ed-ba36-c8cb9e32df8e",1)G
*************************** 1. row ***************************
id: 1
select_type: SIMPLE
table: usergroupnl2
partitions: NULL
type: const
possible_keys: PRIMARY
key: PRIMARY
key_len: 16
ref: const
rows: 1
filtered: 100
Extra: NULL
Copyright @ 2022 Oracle and/or its affiliates.
44

67. MySQL UUID
MySQL generates UUID v1 as described in RFC4122.
UUID v1 : is a universally unique identi er that is generated using a timestamp and the
MAC address of the computer on which it was generated.
UUID v4 : is a universally unique identi er that is generated using random numbers.
Copyright @ 2022 Oracle and/or its affiliates.
45

68. MySQL UUID
MySQL generates UUID v1 as described in RFC4122.
UUID v1 : is a universally unique identi er that is generated using a timestamp and the
MAC address of the computer on which it was generated.
UUID v4 : is a universally unique identi er that is generated using random numbers.
With UUID v4, it's not possible to generate any sequential output.
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45

69. MySQL architectures
new turnkey solutions for HA and DR
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46

70. MySQL InnoDB ReplicaSet
Copyright @ 2022 Oracle and/or its affiliates.
47

71. MySQL InnoDB Cluster
Copyright @ 2022 Oracle and/or its affiliates.
48

72. And now the best of both worlds:
MySQL InnoDB ClusterSet
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49

73. MySQL InnoDB ClusterSet
MySQL InnoDB Cluster with Disaster Recovery !
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50

74. All managed directly from MySQL Shell !
seconds
0
RPO ?
?
RTO
possible rpo>0
rto >
RTO: Recovery Time Objective (how long to
recover)
RPO: Recovery Point Objective (how much
data can be lost)
MySQL InnoDB ClusterSet
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51

75. MySQL Operator for K8s
Kubernetes
Copyright @ 2022 Oracle and/or its affiliates.
52

76. Automated deployment and management of MySQL Server &
MySQL Routers
Self-healing
Backup & Restore
Rolling upgrades with minimal downtime
Developed and supported by the MySQL Team
MySQL Operator for Kubernetes - GA
Both MySQL Operator for Kubernetes & MySQL InnoDB Cluster share a common goal to
make it easier to deploy, automate and manage a service.
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53

77. MySQL Operator for Kubernetes - GA
Copyright @ 2022 Oracle and/or its affiliates.
54

78. MySQL Operator for Kubernetes - GA
The MySQL Operator for Kubernetes is published on GitHub:
h ps://github.com/mysql/mysql-operator
Check out the documentation:
h ps://dev.mysql.com/doc/mysql-operator/en/
Copyright @ 2022 Oracle and/or its affiliates.
55

79. MySQL Shell for VS Code
MySQL in Visual Studio Code
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56

80. MySQL Shell for VS Code
Copyright @ 2022 Oracle and/or its affiliates.
57

81. Visual Studio Code is the most
popular IDE with developers
MySQL Shell for VS Code
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57

82. MySQL Shell for VS Code
Copyright @ 2022 Oracle and/or its affiliates.
58

83. October 16-20
Save the date !
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59

85. MySQL 8.0 DBA Certi cation
Copyright @ 2022 Oracle and/or its affiliates.
61

86. MySQL 8.0 Developer Certi cation
Copyright @ 2022 Oracle and/or its affiliates.
62

87. Thank you !
Copyright @ 2022 Oracle and/or its affiliates.
63