Beginner PHP Tutorial - 122 - More Basic Querying Part 3 Video Lecture | PHP for Absolute Beginners: From Novice to PHP Master - Web Development

we come back to insert and we want to
insert a new value in fact we'll do this
in a query so we want to insert into
users values so we've got our ID we've
got ID our first name out but our using
my password our first name in our last
name so we've got Alex a password Alex
and Garrett
so let's click go now what you can see
is oh ok alright maybe not so let's go
back to operations hmm uh ok so I set it
to zero it needs to be set to 1 sorry so
click go let's come and delete this
query I've just put in there and what
that will do is now when we want to
reinsert some data so insert into users
values ID user name password first name
surname if you set up this structure
first what makes a lot easier to look at
and say just enter your data so password
Alex and Garrett let's click go now you
can see that we've inserted it with a
row ID hmm ok right ok um some reason
this doesn't want to go back
that's odd perhaps we need to delete
before we do this so let's come into
browse and click delete operations come
and change this to one click go let's
just check that's definitely been
changed that's one
yeah it has so let's um let's insert
that again certainly getting lots of
practice inserting how using this SQL so
insert into users values OOP too many
commas
so we've got the username password again
Alex and gap so let's click go
okay so inserted row ID one so if you
were to delete all the data in your
table and you want to start ID one again
then just click on the operations tab
and you can do that from there so these
are some of the basic queries if you
like that we've performed to insert
delete data and modify data and there's
plenty more things you can do things
that you can use joins with combinations
of tables if you're struggling with this
then just have a play around with it
creating data deleting modifying just
selecting from different places as well
we also have things called ordering so
we can order we can order things and
limit things as well now let's just
insert a few more bits of data so user
name Billy password password and then
Billy Karen let's insert some more say
Dale password
kara click go so we've got three bits of
data in here so we're just imagining
that we've got lots and lots of data for
now we've got idea of one two and three
now assuming that ID is one for Alex and
ID is three for Dale Alex will have been
created a lot earlier than Dale we've
created Alex first
then Billy then Dale because we're using
the ideas and ordering system now it's
probably best to use timestamps in this
case and I have a tutorial on timestamps
that you should go back and look at if
you don't already know but when you're
inserting data you should probably
always use a field with a timestamp in
it and therefore what you can do is you
can order order your rows depending on
when that row was created so when the
row was created the timestamp will be
will you know you'll be able to order it
because it's just an integer just a
large integer but for now I'm going to
order using ID now what happens if I
want to order this and display all users
but in order of the last user first so I
want Dale to be first then Billy than
Alex now if you don't know what I mean
I'm going to just going to show you if
we go to select say um first name and
the I could it's surname or last name
let's just have a check at surname say
first name and surname from
users all that's going to do is select
everything so let's just copy and paste
that so we can use it later
let's click go you can see that what's
happened is is we've returned Alex
Garrett Billy Garrett Dale Guerra now
like I said I want to structure this so
Dale is at the top then Billy there Alex
for example you may have a page on your
website that says the new like a member
list and you want to structure your
member list with the newest member at
the top in this case this is ordered in
descending we've started from the first
user and we're just sending down what if
we want it ascending we want to go from
the from the last one and we want to go
up to the top so what we do is we need
to change our query in order to adhere
to this so what we need to do is we need
to do this order by and we want to order
it by a specific column and this column
as we've discussed is ID so order by ID
now it's fair enough ordering by ID but
how are we ordering now we can order by
ascending or descending and it's written
ASC or de SC okay so yeah de SC so I
want to order by ascending first of all
I'm going to click go and you can see
that it's um it's a order date in
ascending order now if I want to descend
from Dale to Alex all I need to do is
make a simple edit to my query and I
want to say order descending in capitals
so we can see what we're doing
so I'm now ordering it in descending
order so if we click go you can see that
Dale's at the top then Billy then Alex
so like I said this could be important
for something a list that you want to
order in a specific order
you could be ordering by say a price or
you could be ordering by a date that
comment was made so if you had a comment
system on your website
you'd be storing comments in a table
you'd assign the dates to a field called
times
and then you can order by that time so
there's many uses for things like
ordering so now what happens if I only
want to show the first two recently
registered users which in this case
would be dial and Billy I can use this
thing called limit the limit keyword so
order by ID descending space limit and
then a number so limit 3 limit to limit
1 if you had lots of records you can say
limit hundred so I'm going to limit by 2
so simple as that limit space to
remember your space after you're
descending as well so we don't need any
sort of commas or anything in between
these we just need spaces so now what
we're doing is we're order it with
selecting the first name in the surname
from users we're ordering by the ID in
descending limits or the so from the
most recently inserted row to the least
M or the first I guess and then we're
limiting by 2 so by clicking this we can
go you can see that we're only returning
the first two rows so I think that's
about all for the most basic queries
things like that that we're going to be
using on a regular basis you will pick
up more as we go along especially inside
PHP when we need to do things like joins
but for now that's basic queries and
I've demonstrated this in PHP myadmin
which is a really good place to mess
around and try things out in an
environment where you can visualize
things rather than going straight into
PHP so if you visualize this first and
have a play around as soon as you
understand it then we can proceed to
doing this but inside PHP