This document provides an overview of the MySQL Cookbook by O'Reilly. It discusses the intended audience of database administrators and developers. It also demonstrates different ways of interacting with MySQL, including through the command line interface, MySQL Shell, and X DevAPI. Examples are provided for common tasks like reading, writing, and updating data in both standard SQL and the object-oriented X DevAPI.

1. MySQL Cookbook
Recipes for Developers
Sveta Smirnova, Percona
Alkin Tezuysal, ChistaDATA

2. l
• MySQL Support Engineer
• Author
MySQL Troubleshooting
MySQL Cookbook, 4th Edition
• JSON UDF functions
• FILTER clause for MySQL
• Speaker
• Percona Live, OOW, Fosdem,
DevConf, HighLoad...
Sveta Smirnova

3. l
SvetaSmirnova
svetasmirnova
@svetsmirnova
svetsmirnova
Let’s Connect!

4. • Audience: DBAs
• They do not write queries
• They tune
• Server options
• Indexes
• Table structure
Sveta the Speaker
4 ©2022 | Percona

5. • For developers
• New topic for me → challenging
• In past I worked as a developer
MySQL Cookbook by O’Reilly
5 ©2022 | Percona

6. • For developers
• New topic for me → challenging
• In past I worked as a developer
• I accepted
MySQL Cookbook by O’Reilly
6 ©2022 | Percona

7. • Queries
sql = "SELECT name, lastname " +
"FROM my_table " +
"WHERE id = " + my_id
15 years ago
7 ©2022 | Percona

8. • Placeholders
sql = "SELECT name, lastname " +
"FROM my_table " +
"WHERE id = ?"
15 years ago
8 ©2022 | Percona

9. • ORM
Speaker(name="Sveta",
lastname="Smirnova").save()
15 years ago
9 ©2022 | Percona

10. • Nothing
Was anything changed?
10 ©2022 | Percona

11. • Nothing
• New MySQL APIs
• Document Store support in MySQL
• Object-oriented query language in MySQL
X DevAPI
Was anything changed?
11 ©2022 | Percona

12. Our Topics Today
12 ©2022 | Percona

13. mysql > SELECT ’Hello, world!’;
+---------------+
| Hello, world! |
+---------------+
| Hello, world! |
+---------------+
1 row in set (0,00 sec)
MySQL CLI
13 ©2022 | Percona

14. • Your SQL code debugger
• Tested by
• Millions of users
• MySQL developers
• Hundreds of tests at every release
• Model API for your query
MySQL CLI
14 ©2022 | Percona

15. MySQL JS > print("Hello, world!")
Hello, world!
MySQL JS > py
Switching to Python mode...
MySQL Py > print("Hello, world!")
Hello, world!
MySQL Py > sql
Switching to SQL mode... Commands end with ;
MySQL SQL > SELECT ’Hello, world!’;
+---------------+
| Hello, world! |
+---------------+
| Hello, world! |
+---------------+
1 row in set (0.0003 sec)
MySQL Shell
15 ©2022 | Percona

16. • New command-line client with X DevAPI
support
• SQL and Object-Oriented queries
• MySQL Server administration
• Utilities
• Replication
• InnoDB Cluster
• Your own applications
MySQL Shell
16 ©2022 | Percona

17. • Asynchronous code execution
• Works with MySQL
• As usual: by executing SQL
• Querying tables as documents
• Collections and documents support
Data storage in JSON
NoSQL-syntax, similar to MongoDB’s
X DevAPI
17 ©2022 | Percona

18. Standard SQL
SQL > SELECT thing, SUM(legs+arms) AS limbs
-> FROM limbs GROUP BY thing
-> HAVING limbs > 5;
+-----------+-------+
| thing | limbs |
+-----------+-------+
| armchair | 6 |
| centipede | 99 |
| insect | 6 |
| squid | 10 |
+-----------+-------+
4 rows in set (0.0004 sec)
Reading
18 ©2022 | Percona

19. X DevAPI for tables
JS > session.getCurrentSchema().
-> getTable(’limbs’).
-> select().groupBy(’thing’).
-> having(’SUM(legs + arms) > 5’)
->
+-----------+------+------+
| thing | legs | arms |
+-----------+------+------+
| armchair | 4 | 2 |
| centipede | 99 | 0 |
| insect | 6 | 0 |
| squid | 0 | 10 |
+-----------+------+------+
4 rows in set (0.0005 sec)
Reading
19 ©2022 | Percona

20. Document Store
Py > session.get_current_schema().
get_collection(’collectionLimbs’).
find(’IFNULL(arms, 0) + IFNULL(legs, 0) > 5’)
{"_id":"000061ed7c240000000000000002",
"arms":0,"legs":6,"thing":"insect"}
{"_id":"000061ed7c240000000000000003",
"arms":10,"legs":0,"thing":"squid"}
{"_id":"000061ed7c240000000000000005",
"arms":0,"legs":99,"thing":"centipede"}
{"_id":"000061ed7c240000000000000007",
"arms":2,"legs":4,"thing":"armchair"}
4 documents in set (0.0004 sec)
Reading
20 ©2022 | Percona

21. Tables and Document Store
JS > session.getCurrentSchema().
-> getCollectionAsTable(’collectionLimbs’).
-> select(’JSON_EXTRACT(doc, "$.thing") AS thing’,
-> ’SUM(IFNULL(JSON_EXTRACT(doc, "$.arms"), 0) +
-> IFNULL(JSON_EXTRACT(doc, "$.legs"), 0)) AS limbs’).
-> groupBy(’thing’).having(’limbs > 5’)
->
+-------------+-------+
| thing | limbs |
+-------------+-------+
| "insect" | 6 |
| "squid" | 10 |
| "centipede" | 99 |
| "armchair" | 6 |
+-------------+-------+
4 rows in set (0.0006 sec)
Reading
21 ©2022 | Percona

22. SQL code in Python
cursor = conn.cursor()
cursor.execute("SELECT id, name, cats FROM profile")
while True:
row = cursor.fetchone()
if row is None:
break
print(f"id: row[0], name: row[1], cats: row[2]")
Working with Results
22 ©2022 | Percona

23. X DevAPI for tables
result = session.get_schema(’cookbook’).
get_table(’profile’).
select(’id’, ’name’, ’cats’).execute()
while True:
row = result.fetch_one()
if row is None:
break
print(f"id: row[0], name: row[1], cats: row[2]")
Working with Results
23 ©2022 | Percona

24. Document Store
result = session.get_schema(’cookbook’).
get_collection(’collectionProfile’).
find().execute()
while True:
doc = result.fetch_one()
if doc is None:
break
print(f"id: doc[’id’], name: doc[’name’], cats: doc[’cats’]")
Working with Results
24 ©2022 | Percona

25. Tables and Document Store
result = session.get_schema(’cookbook’).
get_collection_as_table(’collectionProfile’).
select(’JSON_EXTRACT(doc, "$.id") AS id’).
select(’JSON_EXTRACT(doc, "$.name") AS name’).
select(’JSON_EXTRACT(doc, "$.cats") AS cats’).execute()
while True:
row = result.fetch_one()
if row is None:
break
print(f"id: row[0], name: row[1], cats: row[2]")
Working with Results
25 ©2022 | Percona

26. Standard SQL
INSERT INTO limbs(thing, legs, arms)
VALUES(’cat’, 2, 2);
Changing Data
26 ©2022 | Percona

27. X DevAPI for tables
JS > session.getSchema(’cookbook’).
-> getTable(’limbs’).
-> update().
-> set(’legs’, 4).
-> set(’arms’, 0).
-> where(’thing = "cat"’)
->
Changing Data
27 ©2022 | Percona

28. Document Store
Py > session.get_schema(’cookbook’).
get_collection(’collectionLimbs’).
add_or_replace_one(’00006002f065000000000000006b’,
{"thing": "cat", "legs": 4, "arms": 0})
Changing Data
28 ©2022 | Percona

29. Tables and Document Store
JS > session.getSchema(’cookbook’).
-> getCollectionAsTable(’collectionLimbs’).
-> delete().
-> where(’JSON_EXTRACT(doc, "$.thing") = "cat"’)
->
Changing Data
29 ©2022 | Percona

30. Standard API: establishing connection
conn_params = {
"database": "test",
"host": "localhost",
"user": "sveta",
"password": "",
"charset": "cp1251"
}
conn = mysql.connector.connect(**conn_params)
Character Encoding
30 ©2022 | Percona

31. Standard API: SET NAMES
cursor.execute("SET NAMES utf8mb4")
Character Encoding
31 ©2022 | Percona

32. • X DevAPI
• Only utf8mb4
May not work with your connector!
Character Encoding
32 ©2022 | Percona

33. • When was the longest trip per driver?
+--------+-------+------------+-------+
| rec_id | name | trav_date | miles |
+--------+-------+------------+-------+
| 1 | Ben | 2014-07-30 | 152 |
| 2 | Suzi | 2014-07-29 | 391 |
| 3 | Henry | 2014-07-29 | 300 |
| 4 | Henry | 2014-07-27 | 96 |
| 5 | Ben | 2014-07-29 | 131 |
| 6 | Henry | 2014-07-26 | 115 |
| 7 | Suzi | 2014-08-02 | 502 |
| 8 | Henry | 2014-08-01 | 197 |
| 9 | Ben | 2014-08-02 | 79 |
| 10 | Henry | 2014-07-30 | 203 |
+--------+-------+------------+-------+
Generating Summaries
33 ©2022 | Percona

34. Naive solution
mysql> SELECT name, trav_date, MAX(miles) AS ’longest trip’
-> FROM driver_log GROUP BY name;
ERROR 1055 (42000): ’cookbook.driver_log.trav_date’ isn’t in GROUP BY
mysql> SET sql_mode=”;
Query OK, 0 rows affected (0,00 sec)
mysq> SELECT name, trav_date, MAX(miles) AS ’longest trip’
-> FROM driver_log GROUP BY name;
+-------+------------+--------------+
| name | trav_date | longest trip |
+-------+------------+--------------+
| Ben | 2014-07-30 | 152 |
| Suzi | 2014-07-29 | 502 |
| Henry | 2014-07-29 | 300 |
+-------+------------+--------------+
3 rows in set (0,00 sec)
Generating Summaries
34 ©2022 | Percona

35. Legacy solution
mysql> CREATE TEMPORARY TABLE t
-> SELECT name, MAX(miles) AS miles
-> FROM driver_log GROUP BY name;
mysql> SELECT d.name, d.trav_date, d.miles AS ’longest trip’
-> FROM driver_log AS d INNER JOIN t USING (name, miles)
-> ORDER BY name;
+-------+------------+--------------+
| name | trav_date | longest trip |
+-------+------------+--------------+
| Ben | 2014-07-30 | 152 |
| Henry | 2014-07-29 | 300 |
| Suzi | 2014-08-02 | 502 |
+-------+------------+--------------+
mysql> DROP TABLE t;
Generating Summaries
35 ©2022 | Percona

36. Common Table Expression (CTE)
mysql> WITH t AS
-> (SELECT name, MAX(miles) AS miles
-> FROM driver_log GROUP BY name)
-> SELECT d.name, d.trav_date, d.miles AS ’longest trip’
-> FROM driver_log AS d INNER JOIN t USING (name, miles)
-> ORDER BY name;
+-------+------------+--------------+
| name | trav_date | longest trip |
+-------+------------+--------------+
| Ben | 2014-07-30 | 152 |
| Henry | 2014-07-29 | 300 |
| Suzi | 2014-08-02 | 502 |
+-------+------------+--------------+
3 rows in set (0.01 sec)
Generating Summaries
36 ©2022 | Percona

37. CHECK Constraints
mysql> ALTER TABLE patients ADD CONSTRAINT date_check
-> CHECK((date_departed IS NULL) OR
-> (date_departed >= date_arrived));
mysql> INSERT INTO patients (national_id, name, surname,
-> gender, age, diagnosis, date_arrived, date_departed)
-> VALUES(’34GD429520’, ’John’, ’Doe’, ’M’, 45,
-> ’Data Phobia’, ’2020-07-20’, ’2020-05-31’);
ERROR 3819 (HY000): Check constraint ’date_check’ is violated.
Validation and Formatting
37 ©2022 | Percona

38. JSON Schema for collections
JS > schema={
-> "$schema": "http://json-schema.org/draft-07/schema",
-> "id": "http://example.com/cookbook.json",
-> "type": "object",
-> "description": "Table limbs as a collection",
-> "properties": {
-> "thing": {"type": "string"},
-> "legs": {
-> "anyOf": [{"type": "number"},{"type": "null"}],
-> "default": 0
-> },
-> "arms": {
-> "anyOf": [{"type": "number"},{"type": "null"}],
-> "default": 0
-> }},
-> "required": ["thing","legs","arms"] }
Validation and Formatting
38 ©2022 | Percona

39. JS > collectionLimbs=session.getCurrentSchema().
-> createCollection(’collectionLimbs’,
-> {"validation": {"level": "strict", "schema": schema}})
->
Validation and Formatting
39 ©2022 | Percona

40. Enumerating result
mysql> SELECT
-> ROW_NUMBER() OVER win AS turn,
-> first_name, last_name FROM name
-> WINDOW win
-> AS (ORDER BY RAND());
+------+------------+-----------+
| turn | first_name | last_name |
+------+------------+-----------+
| 1 | Devon | White |
| 2 | Kevin | Brown |
| 3 | Rondell | White |
| 4 | Vida | Blue |
| 5 | Pete | Gray |
+------+------------+-----------+
5 rows in set (0.00 sec)
Sequences
40 ©2022 | Percona

41. Several sequences in one query
mysql> WITH RECURSIVE sequences(id, geo, random) AS
-> (SELECT 1, 3, FLOOR(1+RAND()*5)
-> UNION ALL
-> SELECT id + 1, geo * 4, FLOOR(1+RAND()*5) FROM sequences WHERE id < 5)
-> SELECT * FROM sequences;
+------+------+--------+
| id | geo | random |
+------+------+--------+
| 1 | 3 | 4 |
| 2 | 12 | 4 |
| 3 | 48 | 2 |
| 4 | 192 | 2 |
| 5 | 768 | 3 |
+------+------+--------+
5 rows in set (0.00 sec)
Sequences
41 ©2022 | Percona

42. How many drivers on the road?
mysql> SELECT trav_date, COUNT(trav_date) AS drivers
-> FROM driver_log GROUP BY trav_date ORDER BY trav_date;
+------------+---------+
| trav_date | drivers |
+------------+---------+
| 2014-07-26 | 1 |
| 2014-07-27 | 1 |
| 2014-07-29 | 3 |
| 2014-07-30 | 2 |
| 2014-08-01 | 1 |
| 2014-08-02 | 2 |
+------------+---------+
Joins and Subqueries
42 ©2022 | Percona

43. Missed dates
mysql> CREATE TABLE dates (d DATE);
-> INSERT INTO dates (d)
-> VALUES(’2014-07-26’),(’2014-07-27’),(’2014-07-28’),
-> (’2014-07-29’),(’2014-07-30’),(’2014-07-31’),
-> (’2014-08-01’),(’2014-08-02’);
Joins and Subqueries
43 ©2022 | Percona

44. When drivers have rest?
mysql> SELECT dates.d
-> FROM dates LEFT JOIN driver_log
-> ON dates.d = driver_log.trav_date
-> WHERE driver_log.trav_date IS NULL;
+------------+
| d |
+------------+
| 2014-07-28 |
| 2014-07-31 |
+------------+
Joins and Subqueries
44 ©2022 | Percona

45. CTE: in one query
WITH RECURSIVE dates (d) AS (
SELECT ’2014-07-26’
UNION ALL
SELECT d + INTERVAL 1 day
FROM dates
WHERE d < ’2014-08-02’)
SELECT dates.d, COUNT(driver_log.trav_date) AS drivers
FROM dates LEFT JOIN driver_log
ON dates.d = driver_log.trav_date
GROUP BY d ORDER BY d;
Joins and Subqueries
45 ©2022 | Percona

46. Ranking: legacy way
mysql> SET @rownum := 0;
Query OK, 0 rows affected (0,00 sec)
mysql> SELECT @rownum := @rownum + 1 AS ‘rank‘, score FROM ranks ORDER BY score DESC;
+------+-------+
| rank | score |
+------+-------+
| 1 | 5 |
| 2 | 4 |
| 3 | 4 |
| 4 | 3 |
| 5 | 2 |
| 6 | 2 |
| 7 | 2 |
| 8 | 1 |
+------+-------+
8 rows in set, 1 warning (0,00 sec)
Statistics
46 ©2022 | Percona

47. The issue!
mysql> SHOW WARNINGSG
*************************** 1. row ***************************
Level: Warning
Code: 1287
Message: Setting user variables within expressions is
deprecated and will be removed in a future release. Consider
alternatives: ’SET variable=expression, ...’, or
’SELECT expression(s) INTO variables(s)’.
1 row in set (0,00 sec)
Statistics
47 ©2022 | Percona

48. Ranking: Window Functions
mysql> SELECT ROW_NUMBER() OVER win AS ’rank’, score
-> FROM ranks WINDOW win AS (ORDER BY score DESC);
+------+-------+
| rank | score |
+------+-------+
| 1 | 5 |
| 2 | 4 |
| 3 | 4 |
| 4 | 3 |
| 5 | 2 |
| 6 | 2 |
| 7 | 2 |
| 8 | 1 |
+------+-------+
8 rows in set (0,00 sec)
Statistics
48 ©2022 | Percona

49. Repeating results
mysql> SELECT ROW_NUMBER() OVER win AS ’row’,
-> RANK() OVER win AS ’rank’,
-> score FROM ranks WINDOW win AS (ORDER BY score DESC);
+------+------+-------+
| row | rank | score |
+------+------+-------+
| 1 | 1 | 5 |
| 2 | 2 | 4 |
| 3 | 2 | 4 |
| 4 | 4 | 3 |
| 5 | 5 | 2 |
| 6 | 5 | 2 |
| 7 | 5 | 2 |
| 8 | 8 | 1 |
+------+------+-------+
Statistics
49 ©2022 | Percona

50. Duplicate users
mysql> WITH tmp AS (
-> SELECT COUNT(*) AS count, last_name, first_name
-> FROM catalog_list GROUP BY last_name, first_name HAVING count > 1)
-> SELECT catalog_list.*
-> FROM tmp INNER JOIN catalog_list USING (last_name, first_name)
-> ORDER BY last_name, first_name;
+-----------+------------+----------------------+
| last_name | first_name | street |
+-----------+------------+----------------------+
| Baxter | Wallace | 57 3rd Ave. |
| BAXTER | WALLACE | 57 3rd Ave. |
| Baxter | Wallace | 57 3rd Ave., Apt 102 |
| Pinter | Marlene | 9 Sunset Trail |
| Pinter | Marlene | 9 Sunset Trail |
+-----------+------------+----------------------+
5 rows in set (0,00 sec)
Duplicates
50 ©2022 | Percona

51. • Data type JSON
• Compact storage
• In-place update
On the source and replica
binlog_row_value_options=PARTIAL_JSON
• Operators -> and ->>
• Functions
Search, pattern support
Update
Validation, including JSON schema
Conversion
Documents join
JSON
51 ©2022 | Percona

52. • JSON Path for queries
Names of book authors
mysql> SELECT JSON_EXTRACT(author, ’$.name’) AS author
-> FROM book_authors;
+---------+
| author |
+---------+
| "Paul" |
| "Alkin" |
| "Sveta" |
+---------+
3 rows in set (0,00 sec)
JSON
52 ©2022 | Percona

53. • JSON Path for queries
Names of book authors
mysql> SELECT author->’$.name’ AS author
-> FROM book_authors;
+---------+
| author |
+---------+
| "Paul" |
| "Alkin" |
| "Sveta" |
+---------+
3 rows in set (0,00 sec)
JSON
53 ©2022 | Percona

54. • JSON Path for queries
Removing quotes
mysql> SELECT JSON_UNQUOTE(
-> JSON_EXTRACT(author, ’$.name’)
-> ) AS author FROM book_authors;
+--------+
| author |
+--------+
| Paul |
| Alkin |
| Sveta |
+--------+
3 rows in set (0,00 sec)
JSON
54 ©2022 | Percona

55. • JSON Path for queries
Removing quotes
mysql> SELECT author-»’$.name’ AS author
-> FROM book_authors;
+--------+
| author |
+--------+
| Paul |
| Alkin |
| Sveta |
+--------+
3 rows in set (0,00 sec)
JSON
55 ©2022 | Percona

56. • JSON Path for queries
First and last books
mysql> SELECT CONCAT(author-»’$.name’, ’ ’, author-»’$.lastname’) AS author,
-> author-»’$.books[0]’ AS ‘First Book‘, author-»’$.books[last]’ AS ‘Last Book‘
-> FROM book_authorsG
************************ 1. row ************************
author: Paul DuBois
First Book: Software Portability with imake: ...
Last Book: MySQL (Developer’s Library)
************************ 2. row ************************
author: Alkin Tezuysal
First Book: MySQL Cookbook
Last Book: MySQL Cookbook
************************ 3. row ************************
author: Sveta Smirnova
First Book: MySQL Troubleshooting
Last Book: MySQL Cookbook
JSON
56 ©2022 | Percona

57. Indexes
mysql> ALTER TABLE book_authors
-> ADD COLUMN lastname VARCHAR(255)
-> GENERATED ALWAYS AS
-> (JSON_UNQUOTE(JSON_EXTRACT(author, ’$.lastname’)));
mysql> ALTER TABLE book_authors
-> ADD COLUMN name VARCHAR(255)
-> GENERATED ALWAYS AS (author-»’$.name’);
mysql> CREATE INDEX author_name
-> ON book_authors(lastname, name);
JSON
57 ©2022 | Percona

58. l
Alkin will continue
Thank you!