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Time Narration
00:01 Welcome to mySQL part 5. To echo our data to the user and to display the results from this, we'll need to use "while" statement.
0:12 As I mentioned, we have created a row variable and this is "=mysql_fetch_assoc".
00:21 This is creating an associative array from our "extract" query which is here.
00:27 So we are selecting everything in the "people" table and ordering them by "id" in ascending order.
00:33 Inside our WHILE since we wrote row as an array and its an associative array, row[0] will be wrong because these are numeric.
00:46 These are numeric id tags and instead of this we'll use our fieldnames, since this is associative.
00:59 So, instead of 0 1 2 3 4, we'll be using the actual name.
01:05 Lets create variables from this. Let me say id and then firstname equals, we are using the same structure throughout.
01:15 So its quite easy to copy and paste this.
01:19 Lets indent this.
01:24 So we have 5 altogether.
01:28 So that's five and then lets just change. This is a lazy act!
01:34 But its just a lot quicker to do this way.
01:38 So lastname and we have the date of birth. We also have the gender.
01:47 We have all our data and now how do we use this?
01:51 We need to use the "echo" command.
01:55 There might be a loop inside the middle, at the moment. So anything we echo out will be repeated.
02:02 Every record we have and that's right, too. We'll repeat this code.
02:07 For example, I say text here. There are currently 4 records.
02:13 After refreshing this page, you should see text echoed out 4 times.
02:18 By typing out 4 times, this piece of code here represents every loop.
02:24 Therefore we can incorporate for example, id or firstname or any other, that we have extracted from the database using our associative array.
02:36 Now I'll write firstname lastname was born on dob for date of birth and is and I'll put gender up there.
0 2:49 Not forgetting our linebreak. I'll refresh our page.
02:54 Then we have our set of data structured using the variable names.
02:59 We have given in the correct order and also it has been repeated through for every record we have.
03:08 Okay, we have just given out the content of our table using this star, declared by this asterisk, where it collects every single data or every record.
03:22 Now let me do this. I'll say IF gender==F then gender=female.
03:39 The actual spelling of that and then let us say else gender=male. This is just rewriting the variable depending on the value.
03:50 If we refresh now, we can see this has changed to male male and female female. We also have some interesting ways of displaying this data.
04:00 At the moment I'm selecting from the people table and ordering by id and ascending order.
04:07 I can also order by descending id. You can see that this switches this data around.
04:15 We can also order it by firstname. This will put this in descending alphabetical order and ascending will put this in ascending alphabetical order.
04:33 So we got A D E and K.
04:36 You can do the same with the surname.
04:39 You could do the same with anything. Even Date of birth, as long as you include this over here.
04:46 Another thing to do is, let me just take this back to id and have this as descending. We can use this limit 1 or we can say limit 2, 3 or 4.
04:58 Now I'll limit 1 for the purpose of this.
05:00 Now lets have 1 to let the user of the page know the last person that was inserted into this table.
05:11 So I say "echo" here.
05:16 echo last person to be inserted into table was and I'll leave it like that and add a linebreak.
05:27 I'll just echo out the first and last name. Ok?
05:33 So, here we can see that there is a lot of confusion.
05:38 Last person to be inserted. Yes, in fact it does work!
05:43 It is already typed in the "limit" command.
05:46 What I've done is by limiting this by 1 in descending order of id - the id is incremental - I get 4 at the top and if we are limiting it by 1, 4 will be the only record that is selected.
06:01 Therefore, the last person in the table, as per the last record displayed, will have its value echoed out.
06:09 This "while" will only return 1 data value.
06:13 Since we are returning 1 data value here, we are confused by these.
06:18 This is one command here, so lets" * from people", "order by id decs" is another and "limit 1" is yet another.
06:27 We don't use commas or anything. This is just how we write our code inside our query.
06:34 Okay, just to test this , I'll insert just using the "insert" function in php myadmin and I'll insert another record.
06:45 For example, lets type in "David Green" and our date of birth could be random.
06:55 It doesn't really matter what we type in here. We say male.
07:00 I came down here and submit this data.
07:02 Click on browse and we have a new value here.
07:06 When we come back here and refresh, that will change to "David Green".
07:10 So this is really useful if you have a website in which your putting videos or personal pictures.
07:17 You can just place in the last thing the user had inserted.
07:21 Or may be the last person that has been registered on your website or anything.
07:30 Possibility of using this is endless.
07:33 Basically how to echo out data and how to manipulate it by just using mysql query.
07:44 In the next part, we will allow our user to specify which data they want to show.
07:50 We will create some html forms and to enable them to do this.
07:55 This will let them select a name from the database or table of their choice.
08:00 So, join me in the next part.
08:01 Bye for now. This is Juanita Jayakar dubbing for the Spoken Tutorial Project

Contributors and Content Editors

Minal, PoojaMoolya, Pratik kamble, Sandhya.np14, Sneha