PHP-and-MySQL/C3/MySQL-Part-5/English-timed
From Script | Spoken-Tutorial
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 |