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

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Time Narration
0:00 Hi, welcome back. In this tutorial we will write some data into a database.
0:06 To do this we will use our "mysql query" function.
0:10 Now you can see here that we have our... records....
0:16 I am redoing this tutorial because the first time I did it, it did not work.
0:21 So first of all, I will just delete this data here.
0:29 Well... ok... So we have a blank table, we have no data in our table whatsoever at the moment.
0:36 we can see that there is nothing in here.
0:40 These are just our field names here.
0:43 To begin with, in here, lets just comment this.
0:47 So "write some data". Then we will set up a query that will write data.
0:52 So... "write" and we will use "mysql query" function.
0:59 And this takes exactly 1 parameter which is our sql query.
1:01 To do this, we will type "INSERT" to insert data.
1:06 We are going to say "INSERT INTO".
1:09 Now the reason I've typed this in capitals is because its sql code.
1:14 If I type anything in uppercase it means it is sql code.
1:19 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.
1:30 So "INSERT INTO people" because that is our table name here.
1:34 "INSERT INTO people" and then "VALUES" and then in brackets we will create a little area for each value.
1:40 So we got 1,2,3,4,5.
1:46 There are 5 fields so we need exactly 5 pieces of database written here.
1:50 We need the id, firstname, lastname, all the way down to gender.
1:55 These are created in or created using single quotes each separated by comas.
2:03 The reason we don't use double quotes is because we've got these at the end or rather start and end over here.
2:10 We don't need to insert our id here.
2:13 Our next one is firstname - so I'll say "Alex".
2:17 My lastname I'll say is "Garrett".
2:20 For my date of birth I'll create a date function which equals to a variable "date"
2:26 I'll put this in the particular structure.
2:28 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.
2:39 So on clicking 23rd, we can see the structure this field takes.
2:45 Its the year in long format.
2:47 Next is the month and then the day.
2:48 So 2009 02 23 which is 23rd of the 2nd, 2009.
2:54 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.
3:05 So this will be structured like that.
3:09 This will equal to this and that will be the current date.
3:13 Using the date and presuming that is in the structure of our date, we can insert it into our table here.
3:24 The last one is gender and since I'm a male, I'm putting in "M" for male.
3:28 Presuming that will work, we can run this.
3:30 But before that, we could say "or die" at the end followed by a mysql error.
3:38 I will skip that for now but feel free to add them if you like.
3:44 Ok so refreshing our page.
3:48 What you see is from the last tutorial.
3:50 ummmm..... Lets comment this out.
3:56 Lets ignore this.
3:57 This will completely ignore this part of tutorial.
4:02 Ok - so back to the code that I am currently showing and lets refresh.
4:10 I've refreshed it twice so accordingly 2 records have been put in.
4:14 But by going back to browse and scrolling down we can see, lets delete 1 of these, we can see the data I just specified has been put into the database.
4:26 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.
4:33 I don't want my date of birth as the current date because I was not born today.
4:39 My firstname is ok. My lastname is ok. My gender is fine.
4:43 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.
4:53 You should know that by now.
4:54 Next what I'll show you is how to change my date of birth because I have made a mistake.
5:00 So first I will comment these 2 lines so we don't have to rerun this.
5:04 And I'll create a new variable. We will just comment this as "update data".
5:08 Current variable called "update" and that's equal to "mysql query" function.
5:14 And inside the parameter that we are calling is "mysql query" code itself.
5:20 So here we will type "UPDATE" and we are going to say the table name which is "people".
5:28 Then we will say "SET" and we need to pick a particular field in which to set.
5:34 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.
5:47 By running this command what we are actually doing is we are updating everyone's date of birth in this table to this.
5:54 That's because we've not specified where we want to update this.
5:57 But we can do is after this we can say "WHERE id=6" because my unique id is 6.
6:08 Lets have a look here.
6:10 Otherwise it will update everyone else's.
6:12 Remember I said the id is unique. Its better to say update my id.
6:16 What I could do instead, is say, "WHERE firstname equals Alex". However this will update every record that has firstname "Alex".
6:24 But we can also say "AND lastname equals Garrett".
6:26 However if we still have two people in the database with the same firstname and lastname, we are still running the same risk as before.
6:43 So its best to use our "unique" and thats the key word "unique id" which for me is 6.
6:48 So at the moment, you can see that my date of birth is set to 2009 which is the current date.
6:53 But by refreshing this page, nothing's happened because we are just running a command.
7:00 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.
7:08 So if you need to update data in your database or anything like that, you can specify what data you want to update.
7:15 I used "dob" and that equals to the date of birth that was necessary.
7:18 I could have updated my lastname.
7:20 You also need to specify where you want this to be updated.
7:24 So I said this record which is this long line here.
7:28 These are called records and I specified "WHERE" the id was equal to 6 and that has updated my unique record.
7:35 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.
7:54 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.
8:04 See you soon. This is Juanita Jayakar dubbing for the Spoken Tutorial Project.

Contributors and Content Editors

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