Joomla!: phpMyAdmin for Beginners

phpMyAdmin
for beginners

Presentation “phpMyAdmin for beginners” - http://slideshare.net/yireo
Jisse Reitsma (jisse@yireo.com) - Twitter @yireo

I am Jisse Reitsma
Developer
Enterpreneur
Founder of Yireo
Joomla! & Magento
Extensions & development
Documentation & blogs

Joomla! templates-book (NL)


You are a ...
Joomla! site-owner?
Joomla! builder?
Joomla! developer?


My presentation
Part I - MySQL
Part II - phpMyAdmin
Part III - Advanced

Presentation online: http://slideshare.net/yireo
Tweets: @yireo


Part 1:
MySQL


Introduction to MySQL
Part of a stack
Client/server architecture
What is SQL?


Stack
Joomla! is based on PHP, which runs on a webserver with PHPsupport (like Apache), and data are stored in MySQL.
Examples of webserver “stacks”
Linux + Apache + Mysql + PHP = LAMP
MacOS + Apache + Mysql + PHP = MAMP
Windows + Apache + Mysql + PHP = WAMP
Windows + IIS + Mysql + PHP = WIMP


MySQL server
MySQL on the same server as the website
localhost
On a different server but with the same hoster
mysql12345.hoster.local

On a different server with a different hoster
TCP-port 3306 opened in firewall
Security becomes a major issue


MySQL client
PHP library (“mysql”, “mysqli”, “PDO Mysql”)
Joomla! (PHP “mysqli”)
phpMyAdmin (PHP “mysqli”)
command-line client (SSH)
MySQL GUI client (Navicat, SQLWave, HeidiSQL)


Introduction to MySQL
Part of a stack
Client/server architecture
What is SQL?
Structured Query Language
A way to talk with a relational database


Structured Query Language
A common language to talk with different databases:
SELECT field FROM table
DELETE FROM table WHERE id = 2
INSERT INTO table SET id = 2, value = “example”

... but unfortunately there are still a lot of different SQL dialects


SQL databases
MySQL

SQLite

MariaDB

Sybase

Oracle
Microsoft SQL
DB2

Microsoft Access
dBase

PostgreSQL


Relational database
Store data in multiple database-tabels that relate to each other
Normalisation
“Technique, used in the process of designing a database-structure, with the
purpose to avoid storing the same data multiple times”


Example 1: Joomla! users
jos_users
List of users

jos_usergroups
List of usergroups

jos_user_usergroup_map
Connection between users and usergroups


Example 2: Joomla! articles
jos_content
List of articles (with a reference to catid & asset_id)

jos_categories
List of categories

jos_assets
List of authorizations


Part 2:
phpMyAdmin


phpMyAdmin
Overview of phpMyAdmin
SELECT-statement
Common tasks (edit, add, delete)
Import & export


Login to phpMyAdmin
Direct weblink
Control panel
CPanel, Plesk, DirectAdmin
custom panel


Creating a database
Create an user with corresponding database
Check upon the character collation
utf8_unicode_ci / utf8_general_ci


Opening a database-table


SELECT (1/3)
SELECT * FROM jos_users;
SELECT title,alias FROM jos_content;
SELECT id,username FROM jos_users;
SELECT name,type,enabled FROM jos_extensions;


SELECT (2/3)


SELECT (3/3)


WHERE
SELECT * FROM x WHERE id = 42;
SELECT * FROM x WHERE id IN (42,43,44,45);
SELECT * FROM x WHERE title = “Example 1”;
SELECT * FROM x WHERE title LIKE “Example%”;
SELECT * FROM x WHERE title LIKE “%example%”;
SELECT * FROM x WHERE created_time > “201202”;


Quotes (1/2)
Fout:

SELECT from FROM select WHERE where LIKE “a%”;

Correct:

SELECT `from` FROM `select` WHERE `where` LIKE “a%”;


Quotes (2/2)
SELECT `id`,`title`,`description` FROM `jos_content`
WHERE `title` LIKE “example%” AND `id` IN
(25,26,27,28,29,30) AND `created_time` > “”;


Update, insert, delete
UPDATE jos_content
SET `title`=”Hello World”
WHERE `title`=”Hello world”;
INSERT INTO jos_content
VALUES `title`=”x”;
DELETE FROM jos_content
WHERE `id`=2;


Export
Which database tables?
Single database-table?
Multiple database-table?
All database-tables? (so: the entire database)

Which data?
Table-structure and/or table-data

... or use “Akeeba Backup” (akeebabackup.com)


Part 3:
Advanced


Database table prefix
Database table prefix
Adjustable during Joomla! installation
Make hacks more difficult (SQL-injection)

Recommendations
Do not choose “jos_”
Do not choose “verylongstring_”. MySQL limits table-name to 64 characters


User ID 42
Default “admin” user had ID 42 (Joomla! 2.5 and older)
Make hacks easier (SQL-injection)

Procedure to adjust
Create a new Super User and login as that user
Degrade the old Super User to administrator
Remove that administrator
Update current Super User with old settings

... or use “Akeeba AdminTools” (akeebabackup.com)


Cleanup of database-tables
TRUNCATE `jos_content`;
Be very careful with this
Make sure to have a backup
Make manual checks with other tables


JOINs
LEFT JOIN
RIGHT JOIN
INNER JOIN
OUTER JOIN


Example JOIN
SELECT article.*, cat.title AS cat_title
FROM jos_content AS article
LEFT JOIN jos_categories AS cat
ON cat.id = a.catid
WHERE cat.id = 3;


UTF-8 & collations
UTF-8 = Default character set for Joomla!
Support for Western languages, Arab, Sanskrit, Klingon

Collations = Interpretation of characterset for storage
utf8_general_ci (standard)
utf8_unicode_ci (recommended)
utf8_polish_ci
latin1 (do not use)


Wrong collation
If a Joomla! database does not use UTF-8, make sure it does
(for every database, table and field)
Set Joomla! site offline
Export the datase to a SQL-file
Change all occurances of “charset=latin1 “ to “charset=utf8”
Import the SQL-file

... or use “Phoca Changing Collation Tool” (phoca.cz)


MyISAM & InnoDB
MyISAM Storage Engine
Default in most hosting environments

InnoDB Storage Engine
More advanced; More tuning options
But not necessary for running Joomla!


Alternatives to MySQL
Percona
MariaDb
NoSQL (Redis)


Database optimizations
Make sure to have enough RAM (memory)
Variables
query_cache_size
table_cache, table_size
Vari ous buffers
InnoDB stuff (pool size, threading)

Adjust & monitor; Adjust & monitor


My presentation
Part I - MySQL
Stack; Client/server; SQL

Part II - phpMyAdmin
INSERT, SELECT, UPDATE, DELETE;
Create a database, database-user; Import / export;

Part III - Advanced
JOINs; UTF-8, collations; user-ID 42; MyISAM, InnoDB
TRUNCATE; database table prefix; tuning


tweet @yireo


Joomla!: phpMyAdmin for Beginners

Recommended

Recommended

More Related Content

What's hot

What's hot (6)

Viewers also liked

Viewers also liked (18)

Similar to Joomla!: phpMyAdmin for Beginners

Similar to Joomla!: phpMyAdmin for Beginners (20)

More from Yireo

More from Yireo (20)

Recently uploaded

Recently uploaded (20)

Joomla!: phpMyAdmin for Beginners