‫Welcome back.
‫In this video, I'm going to give you a gentle introduction to Link.
‫And link is used to retrieving data from a data source.
‫And by using a link query operation, you can get data from different types of data sources, and that's
‫exactly what the power of link is all about.
‫So Array's database is XML files and many more sources are valid for a query operation.
‫Let's look at the three parts of a query operation.
‫So obtain a data source, create a query, execute the query.
‫So that's always the three steps that you need in order to actually get some data or adjust some data.
‫So example usage, you should print out the entries of a string array sorted by name.
‫So here we have an array called names and there is Berta, clause and Atom.
‫So the first step is our data source, which is our names string.
‫The second step is the query creation.
‫So we create this query called Var query equals from name in names, order by name, ascending select
‫name.
‫So we go through all the names, then we order them by ascending, which means we get them in an alphabetic
‫order and then we select name.
‫Now what we can do is we can go and create a query execution by using it for each loop where we go ahead
‫and run through every single element of the query and print it out onto the console.
‫So console, right line.
‫And then I so the output will be Adam, Roberta and Klaus.
‫So what we did here is we just reordered the entry of the data that we had and we didn't change the
‫string itself.
‫We just printed it in a different way for us, except usage.
‫You should print out the entries of an entire array sorted by their size, but ignore values that are
‫smaller than five.
‫So here, another one where you see the data source is this numbers array which contains four values
‫7513 and 125, and then of course the four as well, which does not fit our criteria.
‫So the query creation is as follows where query from number in numbers.
‫So we say, okay, we want to check every single number in numbers and we want to go ahead and only
‫use the numbers which are greater than five.
‫And we ordered them descending, which means we go from top to bottom.
‫So from the highest number to the lowest number, and then we select that number.
‫So what our four each two.
‫So our query execution will now give us is the output of 135, 75 and 13.
‫So four will not be included because it doesn't fit our criteria, which was where number creator five
‫So what you can see here.
‫Of course, you can make this a lot more complex.
‫You can get a lot more kinds of limits or filters onto your data.
‫And that's, of course, the power that we have here.
‫Now, this is a very, very gentle and basic explanation of what you can do with Link, but we only
‫looked at arrays.
‫Of course, you can also get the data from different data sources and Lync will behave the exact same
‫way.
‫And that's really the power of Lync because it doesn't care about the data source.
‫It can work with it either way.
‫So it can work with a race.
‫It can work with XML and it can work with databases.
‫And we're going to look into those in more detail, of course, in the following videos.
‫So I hope you enjoy it.
‫It's going to be a more advanced topic, but at the same time you're going to learn to really use the
‫skills that you have acquired so far at a very realistic or real life use.
‫So I hope you enjoy it and see you in the next video.