MySQL Reading Data Video Lecture | PHP for beginners - Software Development

hello YouTube welcome to tutorial number
28 in the PHP programming tutorial
series and in the last tutorial we lock
the how to insert data into a table
using in PHP and my sequel queries and
we insert data into this users to table
and in this video we're going to learn
how to read that data using a PHP MIT
web query and then return that on to a
basic web page for users to view okay so
the first thing we want to do is we have
this users - table we're going to go and
have the name empty this table so go to
your PHP madman and list the tables in
the accounts database and just click on
empty or clear and that will remove all
the records that we have and now what we
need to do is click on insert and we're
going to just insert two Mach values so
the username is going to be M I've no
Jerry Bob and the password is going to
be password and then the first name
going to be
Jerry lastname you want to be let's put
the Smith
Jerry Bob's are very believable name and
then for the second record we're going
to put the username as M I know camera
55 just will highlight things in front
of me right now and password will be
password five the first name will be
John and the last name will be M atom so
we've got Jerry Smith and John atom and
we'll just hit on go down here
okay so we've inserted to mock results
into our database so we just go back
here and and we have Jerry Bob and
camera 55 in our database ready to be
read by our PHP code so the first thing
we need to do is go ahead and open up
your notepad plus plus and I already
saved the file called read PHP because I
just started recording this tutorial and
then I realize that my mic wasn't turned
on telling me what the first thing you
need to do is store variable as
and this is going to be the connection
variable as always we'll call this
accounts and then that's going to equal
my sequel on the score connect and we
have our brackets and set up our
brackets we have a host or username and
our password now for people who are
watching this outside of watching the
whole of my series this will be the
username and password for your my sequel
database and as we've all setup PHP
myadmin
on our localhost we've set our own
username and password - root and
password
I don't know what yours is but the first
one is the host localhost then we have
our username which is root and our
password which is password so these
three things right here will vary
localhost should work unless you're
using an external my sequel database but
excuse me Google should work for most
people
so after this first about or died and
oops my sequel on the score error just
in case you run into any errors okay so
the next thing we need to do as usual
select the database account so my sequel
underscore select on the score DB and
then in brackets the first parameter is
the actual name of the database which is
called accounts and then the second we
need to put our connection which is
accounts the variable accounts okay so
up until now we've all covered these
three lines of code that you should be
starting become quite familiar the
connection variable and then selecting
the database and now is where we use our
my sequel query to M to select data from
a database so we need to first create
our query inside of it just a string and
let me just explain something about this
real quick let me just create this
variable now grate inlets create a
variable called SQL and just leave it
blank for now you just leave it one line
like that we're going to do is create
our my sequel query code so my sequel
bit on the score query and then in
brackets and the first parameter is SQL
which is our query that we're gonna hold
in this string then a comment and the
second parameter is
the connection variable accounts okay so
I wanted to get something in clear where
the blue when I store a SQL query in a
variable appear it doesn't mean you have
to what you can do is where it has m SQL
here the variable you can just simply
put quotations and then type your SQL
query in here what the reason I store it
in a variable up here is because it
looks much more understandable and more
readable to the eye so this you don't
have to store it in a variable you can't
just put it in quotations inside of the
brackets but I find it's easier to just
have a variable a and then in it it's
less confusion it's easier to add it so
now that I've got that all the way what
we're going to do is create a query that
will return some values inside of our
database so first thing we need to do is
specify our my sequel query now you
remember how the my sequel queries where
you know they're pretty much just like
plain text the quite name logical the
syntax of the code and for this only to
do is type select and then the space
what we could do here is type each field
each M field name in sorry each column
separated by commas but what we're going
to do is just type a star sign and what
this will do is select each every single
column from this table so it's going to
select all of the cup all the columns so
we've got M we have ID username password
first and last we'll select all of them
and then we just type the from and now
we need to specify our table and in our
case the table is called users - but you
might obviously have a different table
names so make sure you customize that
according to your my sequel database so
now that we have our query set up here
but there's one change we need to make
from all the other tutorials or need to
do is we need to store the response from
this query inside of a variable so just
here we just type make a variable called
result and just specify that to my
sequel query and then we've got a query
here so if you just go over what we're
doing here and we've obviously connected
up here you guys know what that means
then we've selected the database
accounts inside of this connection well
here what we've done is we've made a new
my sequel query and it just says select
everything from the table uses - and we
just run our query here we run this
query in the connection of accounts okay
so the next thing we need to do is
actually read this response now it's not
what how you think it's not all you know
just a line of text showing all the
results it's actually in this data is
stored in something that we can't read
through plain text so what I need to do
is use a PHP function called my sequel
fetch array so what I'm going to do is
we're going to create a while loop and
this is a moving on a bit you know too
fast but I'll explain and what the my
sequel fetch array does well that's
because we need to look through each
result so we need to just get this all
the way fast
just type while and then just type two
brackets and an opening bracket and a
closing bracket so we have our while
loop here and you guys know as with a
while loop this while loop will run as
long as the condition inside here is
true and what I'm we're going to do in
here we're going to say while role books
role equals and then type my sequel on
the score fetch on the score array and
then in brackets and easy to specify the
variable a hole to the my sequel query
and that is result right here so have
result there on what this will do this
my sequel fetch array function is this
will pass this end result add my sequel
query response and it will just put it
down into an array that we can read and
this while loop will loop through each
time I'm using the first the face while
loop will use the fence row the second
one will use the second row and as soon
as this has reached the end of the rows
it will return false so this in result
will equal to false and then the while
loop will stop so how we reference each
of these in each of the while loops
while it's processing
we do it like this we can do the
variable row and then in square brackets
we type the name of that and field or
column whatever so let's say username if
we type this each time this while loop
runs this roll username will be the
username of that row that it's running
so the first one will be Jerry Bob and
the second one will be camera 55 so and
what we can just do is just echo that
out because we just say echo in row and
then brackets username and what we're
gonna say and we'll just put the name so
we'll just concatenate let's say user
names first name is and then we'll just
have a row first and what this will do
is this will just take the the username
from each field it's kind of getting
really tongue-twisted right now because
of little use walking starts recording
this so I apologize for stuttering go
I'll go back I explain all in a moment
but what this will do is this will
select the username column from here so
it's like the user name from each row
and then it will take the first name as
well and we can just do this with all
them we can just use like in like what
would it easy what you do it would be is
to just declare like username is equal
to row username and then M first is
equal to row first and I'll just store
the variables inside of a easy variable
right here we can just use that set
username and first instead so it's much
easier to read I'm also need a break on
the other that as well okay so just save
that and we need to go to read PHP and
you'll see that says Jerry Bob's first
name is Jerry and camera 55 first name
is John I'm just go back over that and
then just explain it a bit better
because I didn't really
explaining properly and so we have a
connection and we have a select our
database and we've already been over the
query but what this while loop does is
this create a while loop and it creates
a new variable called row and what that
does is uses the PHP function my sequel
fetch array and this will just what this
function will do it will translate the
results into an array so we can just
read it as an array instead of sum in
text that we don't understand in PHP and
then we can loop through that using a
while loop so each time it's going to
have so the first one is going to be the
first result show you the first part of
the array and then the second one is
going to be second part of the array and
the array in this instance is row and
when it comes to the end of the the
lines of rows it will just stop this
will return false and the while loop
will stop so hope that explained it a
bit better
I just I didn't really plan this video
at all just started recording so I
apologize jazz a bit sloppy but in I
really got much time free time to record
this right now so I have to get it done
quickly so yeah that's that's it really
we can also do this to put put it into
like a table so um we could just make a
table pian and we can now that each
table row will hold these a username and
a first name but I don't think I have
time to do that I'll cover all this in
the communtiy tutorials fit down a line
but yeah guys thanks for watching this
tutorial please like and comment and
subscribe and I apologize if it was a
bit and I've studied a lot in this video
i guess i don't know i'm just kinda
confusing myself because i'm just so
tired and i forgot what i was gonna be
covering buh this that's it so leave a
comment and stuff goodbye