Fawks wrote:I have never truly understood what RSS feeds are. Or, for that matter CSS. I can do a little HTML editing, but JAVA, php, flash, SQL just roll on past me. Anyone want to share a little in depth explanation to someone who still uses the cmd prompt for some tasks in winder$ 7?
I did have two semesters of SQL in college but never was taught how to connect a SQL window to html. Two semesters of COBOL?!? Useless.
RSS is a standard for syndicating content (RSS = "Really Simple Syndication."). That is: it's a way for a site to say "here's our content" in some standardised manner. News sites offer stories, or a summary of the story, the forum offers up recent posts. You use some application (Google Reader, was a good example - but NewsBlur isn't too bad an alternative), and that application takes all the feeds you give it, and periodically goes and checks for content.
CSS is a way of styling html markup. It's a way of separating content, from presentation.
To step back a bit, HTML as a way of marking up content on the page.
You have headers, paragraphs, links, images, and a few other ways of giving context about what the content is. On it's own, that 'bare' marked up content has nothing to indicate how it should be presented.
Back in the 'bad old days' of web development, we would add additional markup for all your presentation information: font, font style, font size, background colours, positioning, etc. Every place in the html where you're changing from one place to another (or even a new paragraph) - you'd repeat that styling information. This lead to huge markup with thousands of repetitions, and made editing html difficult. If you decided to change the font size for a header - you'd have to go back everywhere you had a header and edit the markup.
CSS helps here by letting you specify all your presentation information (again, fonts, background images, alignment, etc) in a style sheet. That style sheet can be a seperate file, or can be included in-line with the page. I can change it in one place and it applies everywhere that uses that style sheet.
The 'C' in CSS is for 'Cascading' (the other two are 'style sheet'), meaning that if I can layer styles, and they inherit values from the parent style. For example, I can style links in a particular way (lets say an underline and in hot pink), and when I have a link inside a header - it'll inherit some of the properties from the header (larger font size, bold, and different font face).
Java and PHP are both programming languages - if you've created batch scripts, they're (kinda) just more advanced versions of this.
These are all pretty much identical:
Code: Select all
Batch:
echo Hello World
PHP
print 'Hello World'
Java
System.out.println("hello world");
Some languages are optimised towards doing one thing or another, or being easier to learn.
SQL is a query language for accessing and manipulating data in a relational database management system (RDBMS)
There's an official SQL standard, but all the database engines implement their own variations of that. I use Microsoft SQL Server's T-SQL language most frequently.
Examples of what you can do:
The names of the employees who were employed in the last 30 days
Code: Select all
select name from Employees where EmploymentDate > dateadd(dd, 30, getdate())
The number of employees in each department
Code: Select all
select Department, count(Id) from Employees group by Department
The top 10 employees by sales this year:
Code: Select all
select top 10 e.name, sum(s.SaleTotal) as TotalSales
from Employees e
join Sales s on s.SalesPersonId = e.Id
where s.SaleDate >= '2013-01-01'
group by e.Id
order by sum(s.SaleTotal) desc
Give any employee who made at least $5000 this year in sales a 5% pay rise:
Code: Select all
update Employees
set Salary = Salary * 1.05
from Employees e
join (select SalesPersonId, sum(SaleTotal) as TotalSales from Sales where SaleDate >= '2013-01-01') summary on e.Id = summary.SalesPersonId
where summary.TotalSales >= 5000
I use C# and SQL daily (This is my day job), so I'm pretty comfortable with them.
