PHP-and-MySQL/C3/MySQL-Part-3/English-timed

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Time Narration
00:00 Hi, welcome back. In this tutorial you will write some data into a database.
00:07 To do this we will use "mysql query" function.
00:12 Now you can see here that we have our... records.
00:16 I am redoing this tutorial because the first time I did it, it did not work.
00:22 So first of all, I will just delete this data here.
00:29 Well... ok... So we have a blank table, we have no data in our table whatsoever at the moment.
00:37 we can see that there is nothing in here.
00:40 There are just our field names here.
00:43 To begin with, in here, let's just comment this.
00:47 So, "write some data". Then we will set up a query that will write data.
00:52 So... "$write" and we will use "mysql-query()" function.
00:57 And this takes exactly 1 parameter which is our sql query.
01:02 To do this, we will type "INSERT" to insert data.
01:06 We are going to say "INSERT INTO".
01:09 Now the reason I've typed this in capitals is because it's sql code.
01:14 If I type anything in uppercase it means it is sql code.
01:19 If I type anything in lowercase it means its either a table name, database name or it is data that I'm writing to the database.
01:28 So, "INSERT INTO people" because that is our table name here.
01:33 "INSERT INTO people" and then "VALUES" and then in brackets we will create a little area for each value.
01:42 So, we got 1,2,3,4,5.
01:46 There are 5 fields, so we need exactly 5 pieces of database written here.
01:53 We need the id, firstname, lastname, all the way down to gender.
01:58 These are created in or created using single quotes each separated by coma.
02:07 The reason we don't use double quotes is because we've got these at the end or rather start and end over here.
02:15 We don't need to insert our id here.
02:18 Our next one is firstname - so I'll say "Alex".
02:22 My lastname I'll say is "Garrett".
02:25 For my date of birth, I'll create a date function which equals to a variable "$date"
02:31 I'll put this in the particular structure.
02:35 We can see from our database over here that when we go to insert a value, we can scroll down and see that our calender function has dates on it.
02:44 So, on clicking 23rd, we can see the structure this field takes.
02:50 It's the year in long format.
02:52 Next is the month and then the day.
02:55 So 2009 02 23 which is 23rd of the 2nd, 2009.
03:02 So, what we can do here is, we can structure our date function in capital 'Y', 'm' and then 'd' using hyphen in between to get the structure we need.
03:13 So, this will be structured like that.
03:16 This will equal to this and that will be the current date.
03:20 Using the $date and presuming that is in the structure of our date, we can insert it into our table here.
03:28 The last one is gender and since I'm a male, I'm putting in "M" for male.
03:34 Presuming that will work, we can run this.
03:37 But before that, we could say or die at the end followed by "mysql_error".
03:44 I will skip that for now but feel free to add them if you like.
03:50 Ok, so refreshing our page.
03:53 What you see is from the last tutorial.
03:57 ummmm..... Let's comment this out.
03:59 Let's ignore this.
04:01 This will completely ignore this part of tutorial.
04:08 Ok - so back to the code that I am currently showing and let's refresh.
04:14 I've refreshed it twice. So, accordingly 2 records have been put in.
04:24 But by going back to browse and scrolling down we can see, let's delete 1 of these, we can see the data 1 just specified, has been put into the database.
04:35 In fact, what I have done is I have put my date of birth as the current date which I didn't mean to do.
04:43 I don't want my date of birth as the current date because I was not born today.
04:48 My firstname is ok. My lastname is ok. My gender is fine.
04:53 We can see that my id is 6 at the moment and the next time we insert a record this would go up to 7 and then again to 8.
05:02 You should know that by now.
05:03 Next what I'll show you is how to change my date of birth because I have made a mistake.
05:09 So, first I will comment these 2 lines so we don't have to re-run this.
05:15 And I'll create a new variable. We will just comment this as "update data".
05:20 Current variable called "$update" and that's equal to "mysql_query()" function.
05:26 And inside the parameter that we are calling is mysql query code itself.
05:32 And here you will type "UPDATE" and we are going to say the table name which is "people".
05:38 Then we will say "SET" and we need to pick a particular field in which to set.
05:43 This happens to be the "d o b" and that's equal to my actual date of birth which is 1989, the year I was born in and the month is November and the day I was born is 16th.
05:57 By running this command what we are actually doing is we are updating everyone's date of birth in this table to this.
06:05 That's because we've not specified where we want to update this.
06:10 But we can do is after this we can say "WHERE id=6" because my unique id is 6.
06:18 Let's have a look here.
06:23 Otherwise it will update everyone else's.
06:26 Remember I said the id is unique. It's better to say update my id.
06:32 What I could do instead is, say, "WHERE firstname equals 'Alex' ". However this will update every record that has firstname "Alex".
06:41 But we can also say "AND lastname equals Garrett".
06:46 However, if we will have two people in the database with the same firstname and lastname, we are still running the same risk as before.
06:54 So, it's better to use our "unique" and that's the key word "unique id" which for me is 6.
07:00 So at the moment, you can see that my date of birth is set to 2009 which is the current date.
07:06 But, by refreshing this page nothing's happened because we are just running a command.
07:11 Now, if we click on Browse to refresh and we scroll down, we can see that it has changed to what we specified and everything else has been left intact.
07:21 So, if you need to update data in your database or anything like that, you can specify what data you want to update.
07:29 I used "dob" and that equals to the date of birth that was necessary.
07:34 I could have updated my lastname.
07:36 You also need to specify where you want this to be updated.
07:40 So, I said this record which is this long line here.
07:46 These are called records and I specified "WHERE" the id was equal to 6 and that has updated my unique record.
07:56 So that's what you have learnt - how to insert values and also how to update some values if you get it wrong like I did or if you just want to update some data which happens most of the time when your doing your databases.
08:10 Ok - so join me in the next part to find out how to start reading from your database and display the data to the user.
08:17 See you soon. This is Juanita Jayakar, dubbing for the Spoken Tutorial Project.

Contributors and Content Editors

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