1. Would You Like Some Transactions With That Table?
MySQL
Would You Like Some Transactions
With That Table?
Oct 29, 2009

2. Slides Are Available
Oct 29, 2009

3. What Is MySQL? Most popular open source RDBMS Widely used
Open source means 'free'
Really? No cost at all?
Widely used
Sabre – airline reservations
Google
LinkedIn
What does Oracle DBA need to know?
Many differences...
Oct 29, 2009

4. Why Should I Care? I'm an Oracle DBA Why should I learn about MySQL?
MySQL means nothing to me
It isn't a 'real' RDBMS
Why should I learn about MySQL?
MySQL is being used by real businesses
Can't hurt your employability
Many jobs expect DBA to know multiple RDBMS
Why not learn one that is widely used?
And it's free – you can download and install right now!
Oct 29, 2009

5. Oracle DBA Perspective
What will we look at?
Installing
Start/stop
How database/tables stored
Backups
Transactions
Storage engines
Oct 29, 2009

6. My Message Compare MySQL to Oracle Not to be critical of MySQL
Not to praise Oracle
Make Oracle DBAs aware
How much we assume about RDBMS
Because Oracle does things a certain way
MySQL is very different
Assuming it is like Oracle can cause serious problems
Does your business understand the differences?
The cost of being 'free'?
Oct 29, 2009

7. MySQL Versions MySQL Enterprise MySQL Community Edition
Have to buy support
MySQL Community Edition
The 'free' version
MySQL Community Edition Preview Release
Available for download
Ready for prime time?
Oracle doesn't offer 12g for trial download...
Oct 29, 2009

8. MySQL Versions
Oct 29, 2009

9. MySQL – Where Did It Come From?
Used to store web site logs
Transactions
What's that?
If we lose some records
So what?
Supported by an individual
Do your own thing
Recovery
Not to worry, plenty more web logs every day
Oct 29, 2009

10. Some Differences – MySQL/Oracle
Database
Schema
a group of database objects
Database user
Maps to a database schema
MySQL
Server
Databases
Group of database objects
Users don't map to database
Oct 29, 2009

11. Some Differences – MySQL/Oracle
Storage engines
Transaction support
Performance
Hot backup
Binary logging and recovery
Table locking
Corruption
Misc.
Oct 29, 2009

12. Storage Engines MySQL gives you a choice MySQL storage engines
Oracle, all transactional all the time (OATATT)
MySQL storage engines
MyISAM (IBM, Indexed Sequential Access Method)
Very fast read
InnoDB
Transactional, like Oracle
Separate software, owned by Oracle
Many others
See next chart
Oct 29, 2009

13. Storage Engines
Oct 29, 2009

14. InnoDB Storage Engine Imagine mixing
MyISAM, InnoDB tables in a statement
What does 'transactional' mean?
What does “recovery” mean?
Oct 29, 2009

15. CSV Storage Engine CSV storage engine Stores data in text files
Using comma-separated format
Oct 29, 2009

16. Blackhole Storage Engine
My favorite
This is where we store all the data relating to the Raiders and
their 'Commitment to Excellence'
Oct 29, 2009

17. Yeah, But... No problem Cool, but I'll just make all the tables InnoDB
MySQL catalog (system?) tables are MyISAM
Can't change them
Table storage engine can be changed at any time
Privileged users
No one should do this, but...stuff happens
Create table syntax
Supports overriding default storage engine
Oct 29, 2009

18. Transaction Support MyISAM Default table type
Table type of system databases
Does not support transactions
Example
Writing to MyISAM tables and server crashes
Who know what was and wasn't written to tables
No recovery
Oct 29, 2009

19. Performance Many large MySQL servers in use Optimizer
Performance must be good
or good enough for 'free'
Optimizer
Different storage engines
How to optimize statement that has
MyISAM tables
InnoDB tables
Does it support all storage engines you are using?
Oct 29, 2009

20. Hot Backup MySQL does not have this Backup option #1 Backup option #2
Shutdown server, copy all files, startup server
Backup option #2
Lock all tables
Dump all data to a dump file
Dump file is set of SQL to recreate database
Very slow to recover
Backup option #3
Buy hot backup software product
Not free
Oct 29, 2009

21. Binary Logging and Recovery
MySQL
Default, no logging
You can configure binary logging
Three formats
Statement-based
Row-based
Mixed
Binary log filenames have format
binlog , binlog , etc.
You must apply them in correct order
Oct 29, 2009

22. MySQL Binary Logs
MySQL does not have any way of knowing when replaying the binary logs which statements need to be executed and which are already committed.
Oracle DBA doesn't worry about this
Oracle checks and tells you which archived redo log is needed next
Oracle won't allow archived redo logs to be applied out of order
Oct 29, 2009

23. Binary Logging Formats
Oct 29, 2009

24. Binary Log Issues
Oct 29, 2009

25. Table Locking MyISAM storage engine InnoDB storage engine
Does not support row level locking
Table locks
Performance?
InnoDB storage engine
Supports row level locking
Oct 29, 2009

26. Corruption Oracle MySQL I have rarely seen any cases
But all tables support transactions
MySQL
What does it mean to rollback
When different storage engines involved
Some support transactions, some don't
Some tables will be rolled back
Others won't
Is this corruption?
Oct 29, 2009

27. MySQL Corruption Issues
Good read
Discusses corruption issues in MySQL engines
I'm not saying this happens often
But you need to be aware of these issues
Another difference from Oracle
Different storage engines, different corruption mechanisms
/30/mysql-crash-recovery/
Oct 29, 2009

28. MySQL Issues Misc Referential Integrity Triggers Directload
Some storage engines support
Triggers
Row-level, not statement-level
Directload
Not supported
Parallel Query
Oct 29, 2009

29. MySQL Issues White Paper Compares MySQL to PostgreSQL
PostgreSQL, another open source RDBMS
More like Oracle than MySQL
Discusses issues with MySQL
I'm not endorsing PostgreSQL
But the whitepaper is very good
Google
PostgreSQL vs. MySQL A Comparison of Enterprise Suitability
Oct 29, 2009

30. MySQL Table Storage MyISAM InnoDB Each table has three files
<filename>.frm – Data dictonary information
<filename>.MYD – table data
<filename>.MYI – table indexes
InnoDB
Data and indexes in a tablespaces
Made up of one or more datafiles
Sound familiar?
Oct 29, 2009

31. Documentation Online
Oct 29, 2009

32. Documentation Online
Oct 29, 2009

33. Documentation Online
Oct 29, 2009

34. Talk Is Cheap A little less conversation
A little more action
Download and install MySQL to your laptop now
Slides show the steps
Windows
You will have a fully functional MySQL server
Start learning right now
Oct 29, 2009

35. Install MySQL – Windows
Windows Vista
6.0 Service Pack 1
Screenshots shown
Windows XP
Professional Version 5.1
Same steps
Very minor differences in what you see
Oct 29, 2009

36. Downloads?
Oct 29, 2009

37. Downloads?
Oct 29, 2009

38. Enterprise Version
Oct 29, 2009

39. Community Version
Oct 29, 2009

40. Windows Downloads
Oct 29, 2009

41. Windows Installation
Oct 29, 2009

42. Windows Installation
Oct 29, 2009

43. Windows Installation
Oct 29, 2009

44. Windows Installation
Oct 29, 2009

45. Windows Installation
Oct 29, 2009

46. Windows Installation
Oct 29, 2009

47. Windows Installation
Oct 29, 2009

48. Windows Installation
Oct 29, 2009

49. Windows Installation
Oct 29, 2009

50. Windows Installation
Uncheck
Oct 29, 2009

51. Windows Installation
Oct 29, 2009

52. Windows Installation
Check
Oct 29, 2009

53. Windows Installation
Oct 29, 2009

54. Windows Installation
mysql
Oct 29, 2009

55. Windows Installation
Oct 29, 2009

56. Accessing MySQL Windows
Click Start
Programs
MySQL
MySQL Server 5.1
MySQL Command Line Client
Right-click
Send to
Desktop (Create Shortcut)
Double-click desktop icon
Oct 29, 2009

57. Accessing MySQL Windows
Shortcut created at installation
mysql
Oct 29, 2009

58. mysql client utility
Similar to SQL*Plus
Oct 29, 2009

59. Now What? Stop, start MySQL server What databases are available
show databases;
Set default database
use <dbname>
What tables are in the database
show tables;
Oct 29, 2009

60. Windows Vista Stop/Start Services Start Settings Control Panel
System and Maintenance
Administrative Tools
Scroll down to MySQL, highlight
Upper left, options for Stop, Pause, Restart
If MySQL is down, option to Start
Oct 29, 2009

61. Windows XP Stop/Start Command line Services
net stop mysql, net start mysql
Services
Start
Control Panel
Administrative Tools
Services window
Scroll down to MySQL, highlight
Upper left, options for Stop, Pause, Restart
If MySQL is down, option to Start
Oct 29, 2009

62. Oct 29, 2009

63. Oct 29, 2009

64. System Databases INFORMATION_SCHEMA MYSQL database TEST
Catalog database
MYSQL database
User and privilege information
TEST
For you to play in...
These databases are created at installation
Oct 29, 2009

65. MySQL Server Configuration
Controlled by 'option' file(s)
Similar to Oracle pfile or spfile
SHOW VARIABLES
See current values
Standard location(s)
Search order
One of the most common problems
Persons don't know where these files are
Make changes that don't take affect
Can't find the file or files
Oct 29, 2009

66. Option File(s) MySQL searches multiple locations
Uses most recent value of each parameter
How to know all files being scanned by MySQL?
mysql –help
Note: dash dash help
Oct 29, 2009

67. Option File
Oct 29, 2009

68. Option File
Oct 29, 2009

69. Option File
Oct 29, 2009

70. Option File
Oct 29, 2009

71. Option File
Oct 29, 2009

72. MySQL Filesystem Layout
From option file (my.ini)
basedir
Where software is stored
datadir
Where table data is stored
Oct 29, 2009

73. MySQL basedir
Oct 29, 2009

74. MySQL basedir/bin
Oct 29, 2009

75. MySQL datadir
Oct 29, 2009

76. MySQL Log Files General Query Log Binary Log Slow Query Log Error Log
All client requests
Binary Log
Statements that modify data
Slow Query Log
Statements that take longer than 10 seconds
Error Log
Server messages
Oct 29, 2009

77. MySQL Log Files
Find log file locations
Oct 29, 2009

78. Summary MySQL is 'free' MySQL is widely used
May need other products to make it work for you
Hot backup for example
MySQL is widely used
MySQL is very different from Oracle
DBA tasks and issues will be different
MySQL is not better or worse than Oracle
Just very different
Oct 29, 2009

79. The End? You now have a MySQL server installed No excuses Next?
Learn it, live it, love it
Update your resume
Next?
Multiple MySQL servers on same machine
Replication
etc.
Oct 29, 2009