1. MySQL Essentials
2012
Chris Henry
@chrishnry
Sunday, January 20, 13

2. hello.
Sunday, January 20, 13

3. MySQL @ Behance
Powers Be.net
17 Dell R710s
120GB
XFS Filesystem
Percona 5.5
Sunday, January 20, 13

4. What Version of MySQL?
- Does it actually matter? Fuck yes.
mysql> SELECT VERSION()
Welcome to the MySQL monitor.
Your MySQL connection id is 54248515
Server version: 5.5.24-55-log Percona Server (GPL),
Release rel26.0, Revision 256
Sunday, January 20, 13

5. Percona
• Why?
http://www.percona.com/
• Percona Toolkit
http://www.percona.com/software/percona-
toolkit
Sunday, January 20, 13

6. MySQL Engines
• Pluggable architecture.
• INNODB vs MyISAM
• Transactions
• Locking
• Fulltext
• Should be InnoDB for most things
http://dev.mysql.com/doc/refman/5.5/en/
storage-engines.html
Sunday, January 20, 13

7. Configuration
• table_open_cache
• innodb_buffer_pool
• max_connections
• key_buffer_size
Sunday, January 20, 13

8. Slow Log
my.cnf
slow-query-log-file = /var/lib/mysqllogs/slow-log
long-query-time = 2
Sunday, January 20, 13

9. Tuning - Easy Wins
• skip-name-resolve
• Linux Swappiness
Sunday, January 20, 13

10. Slow Log Output
# Query_time: 0.015029 Lock_time: 0.000044 Rows_sent: 481
Rows_examined: 5080 Rows_affected: 0 Rows_read: 481
# Bytes_sent: 4888 Tmp_tables: 1 Tmp_disk_tables: 0
Tmp_table_sizes: 126992
# Filesort: Yes Filesort_on_disk: No Merge_passes: 0
# InnoDB_IO_r_ops: 0 InnoDB_IO_r_bytes: 0
InnoDB_IO_r_wait: 0.000000
# InnoDB_rec_lock_wait: 0.000000 InnoDB_queue_wait:
0.000000
SELECT DISTINCT proj.id
FROM projects proj
INNER JOIN project_summary ps ON proj.id=ps.proj_id
WHERE proj.published = 1 AND proj.privacy2 = 1
ORDER BY ps.apps DESC
LIMIT 0, 481;
Sunday, January 20, 13

11. EXPLAIN Output
*************************** 1. row ***************************
id: 1
select_type: SIMPLE
table: proj
type: ref
possible_keys: PRIMARY,published,privacy2,
key: privacy2
key_len: 2
ref: const,const
rows: 1
filtered: 100.00
Extra: Using index; Using temporary; Using filesort
*************************** 2. row ***************************
id: 1
select_type: SIMPLE
table: ps
type: ref
possible_keys: proj_id
key: proj_id
key_len: 4
ref: be_net2.proj.id
rows: 1
filtered: 100.00
Extra: Distinct
2 rows in set, 1 warning (0.00 sec)
Sunday, January 20, 13

12. Table Design
• Data Types
• Relations
• Normal Form
Sunday, January 20, 13

13. Data Types
• Right tool for the job
• Numeric
• String
• Temporal
• Spatial
Sunday, January 20, 13

14. Integer Data Types
• How big?
• Signed or unsigned?
• What the hell does that number in parens
mean?
• Integer types are great for storing things like
type attributes.
Sunday, January 20, 13

15. Integer Table
CREATE TABLE IF NOT EXISTS `integers` (
`tiny` tinyint(4) NOT NULL,
`tiny_zerofill` tinyint(10) unsigned zerofill NOT NULL,
`small` smallint(6) NOT NULL,
`medium` mediumint(9) NOT NULL,
`int` int(11) NOT NULL,
`int_unsigned` int(10) unsigned NOT NULL,
`big` bigint(20) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
Sunday, January 20, 13

16. Decimals
• Fixed Point
• DECIMAL (5,2)
Sunday, January 20, 13

17. Text Datatypes
• CHAR (0 to 255)
• VARCHAR (0 to 65,535) + length
Sunday, January 20, 13

18. Bigger Text Datatypes
• TINYTEXT
• TEXT
• MEDIUMTEXT
• LONGTEXT
http://dev.mysql.com/doc/refman/5.5/en/string-type-overview.html
Sunday, January 20, 13

19. Character Sets + Collation
• A Character Set is a set of symbols and
encodings.
• Collation is the set of rules for comparing
characters.
• utf8 / utf8_unicode_ci is best bet for most
Western languages.
Sunday, January 20, 13

20. Temporal
• DATE
• TIME
• DATETIME
• TIMESTAMP
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-types.html
Sunday, January 20, 13

21. Table Design
• Primary Key
• Compound Keys
• Indexes
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-types.html
Sunday, January 20, 13

22. Querying
• Sakila Database
• DVD Rental Store
http://dev.mysql.com/doc/sakila/en/index.html
Sunday, January 20, 13

23. That’s it!
Thank you all for coming!
Feedback is welcome!
Sunday, January 20, 13