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MySQL module S152
SQL Primer as Used in MySQL
Exercises, examples and other material relating to training module S152. This topic is presented on public courses Deploying LAMP - Linux, Apache, MySQL, Perl/PHP, Linux Web Server, MySQL, Deploying Java Applications on Linux / Unix

The Structured Query Language provides the application programmer interface that allows data to be entered into, edited, and selected from most relational databases. It also provides users with suitable authorisation with the ability to create and edit the structures that hold the data.

Related technical and longer articles
MySQL joins - using left join and right join to find orphan rows
Left Joins to link three or more tables

Articles and tips on this subjectupdated
4007Which database should I use? MySQL v SQLite
Which SQL Database would I advise newcomers with a new application to use? Five years ago, MySQL would have been the obvious choice in many circumstances. But these days, MySQL has grown into a much bigger product and there are very serious licensing and other commercial issues that need to be considered; ...
In a database such as MySQL, data is divided into a series of tables (the "why" is beyond what I'm writing today) which are then connected together in SELECT commands to generate the output required. I find when I'm running MySQL training, people often get confused between all the join flavours. Let ...
3061Databases - why data is split into separate tables, and how to join them
If you're travelling from Chippenham to London by train, you may want to grab a quick coffee at the station before you set off - and where better than Steamers? And if you were traveling to Plymouth, Bristol, Southampton, Llandrindod Wells or Cheltenham, you would use Steamers too. Let's assume I'm ...
3060INSERT, DELETE, REPLACE and UPDATE - changing the content of SQL tables
Most enquires of an SQL database are SELECTs - most database are "Read Mostly" and writes are limited to a small proportion of accesses (though there are exceptions). And SELECTs are much more complex that things that insert or change data too. However, I found myself writing en example on yesterday's ...
2240How do I query a database (MySQL)?
From my mailbox ... "What are the different ways of queries in databases? Could u pls explain each way in more detail? thanks" The term "query" means something a little bit different in the term "SQL" to it does in regular English usage - the dictionary definition is to ask for information / pose a ...
515MySQL - an FAQ
We're becoming a serious MySQL resource, with many technical articles, examples, forum posts and blog entries answering those difficult-to-resolve issues you may have come across. You might like to bookmark (or link to) this page. Eleven recent articles on MySQL ... Flashbulb moments - facts that ...
591Key facts - SQL and MySQL
Some quick ways to remember your SQL; here are some "flashbulb moments" for newcomers and occasional users of MySQL and other SQL databases. A database daemon is a process that looks after a number of DATABASES each of which comprises a number of TABLES each of which comprises data arranges in ROWS ...
270NULL in MySQL
NULL is not a value - it's a condition. So if you try and write something "= NULL" you'll get an empty set rather than the results you're looking for. Try "IS NULL" instead. example Joining 2 tables connecting records that match mysql> select * from demo_people join demo_property on demo_people.pid ...
Examples from our training material
joiner.sql   Create two tables, link them with left join
linked.sql   Two tables ... an illustration of the different joins
loader.sql   Loading data from csv files
make_dvd.sql   Create a database and table for a DVD collection
pop_dvd.sql   Insert rows into sample dvd table
seeds.mysql   MySQL example - table joins
sql_demo.sql   Adding and amending data in a database table
tab1   First table for advanced join demos
tab2   Second table for advanced join demos
MySQL training
Training for Oxford University Computer Services
Background information
You may download this module as a sample of our material
Topics covered in this module
The structure of a database as seen by SQL.
SQL introduction.
Hello SQL World.
Initial administration and error handling.
Field types and modifiers in MySQL.
Floating point (real) numbers.
Whole (Integer) numbers.
Text Strings.
One or more values from a pre-defined list.
Dates and Times.
Other Modifiers.
Other matters.
A note on reserved words.
Commands to enter new rows of data.
The INSERT command.
The REPLACE command.
The LOAD command.
Enquiry commands.
Conditional Clauses.
Returning table report information.
Commands to modify existing rows of data.
The UPDATE command.
The DELETE command.
Commands to modify the metadata.
The ALTER Command.
The DROP command.
Other commands.
The SHOW command.
On limiting selection.
Joining tables when selecting rows.
Extra use of SELECT.
Other commands.
Some more advanced SQL.
Loading data from file.
More on joining.
A regular "join".
A left join.
Joining across databases?.
Complete learning
If you are looking for a complete course and not just a information on a single subject, visit our Listing and schedule page.

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