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Now that we have successfully run a query, we need to take a closer look at what is returned to us by our query method. All of the return data comes back to us in the form of a PDO Statement object.
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Now that we have successfully run a query,
0:00
we need to take a closer look at what is
returned to us by our query method.
0:02
All of the return data comes back to us in
the form of a PDO statement object.
0:06
Okay continuing, we're going to get rid of
this exception that we have here.
0:12
It's refreshed I've already fixed it in
the file.
0:17
So refresh this and we're back to our PDO
statement object showing the query string.
0:19
And we need to extract the results from
this.
0:25
We wanna get, get all of our films out of
our PDO statement object.
0:29
And the first place I would say check is
we go to our documentation and
0:34
look up the PDOStatement object.
0:38
I'm just gonna actually copy this and
paste it and hit enter, and
0:40
that will take us to the manual page for
the PHP PDOStatement.
0:46
So, here is our PDOStatement class.
0:51
It, says it represents a prepared
statement and
0:54
after it is executed, the associated
results set, so
0:57
that is what we're gonna work with is our
associated results set.
1:01
We're gonna go on down and
1:05
look at the methods and the method that
we're gonna want here.
1:06
Let's say we could do fetch, fetch, fetch
all.
1:11
Yeah, that sounds good, fetch everything.
1:14
This says it returns an array containing
all the result set rows.
1:16
So it's going to return to us an array,
and
1:21
it doesn't have any required arguments.
1:25
So let's go ahead and run that method.
1:26
On our results object which is a instance
of the PDOStatement object.
1:29
And back over to our code, we're gonna go
down here and
1:35
we're gonna work with this results set.
1:38
So here I'm gonna continue to var_dump and
1:41
then die our result set, but we want to
use the fetch all method.
1:43
Before we dig into our fetch all method
and
1:49
see what it's gonna return to us, we wanna
get rid of that error or
1:51
the possibility of an exception being
thrown by the query being incorrect.
1:55
The way we're gonna do that is with
wrapping it in a try catch block.
2:01
So we'll go ahead up here to line four,
2:05
come down a little bit, and wrap this in a
try block.
2:07
Try no arguments.
2:11
I'm gonna tab this in.
2:14
All right.
2:18
Close this guy out, and then open up
catch.
2:19
And we are still going to catch the
Exception class, and
2:24
pass it through to an object $e, close it
out.
2:29
And in here the same thing as before.
2:34
We're just going to echo out our exception
object, which is $e.
2:36
And the method that we're going to use is
going to be
2:42
the same as before, getMessage.
2:45
Okay, pass that through just to make sure
that our try-catch block is working.
2:50
We'll again, get rid of our correct
statement and then refresh.
2:55
And then now you'll see it says General
Error.
3:00
That's saying it's our syntax error.
3:03
That's exactly what we wanted to see,
3:05
except we didn't want to see the rest of
this.
3:07
So we need to add a die statement to the
end of this.
3:10
Okay, so let's refresh again.
3:16
There we go much better.
3:19
It just kills it, and gives us the actual
error itself.
3:20
That's exactly what we're looking for.
3:23
All right, let's go back in and fix our
statement here.
3:26
Select, all right save that.
3:31
Double check that we're back to working.
3:35
And we are, great.
3:37
Now instead of just dumping the results,
3:39
we're going to use that method that we
looked at which is fetch all.
3:41
So, object operator, fetch, capital A for
fetchAll.
3:46
And then open and close parens with no
arguments and let's go see what it does.
3:51
Hit refresh.
3:56
All right.
We have an array with a thousand results.
3:58
That's a lot.
4:02
And it's really hard to look at right now,
4:02
so let's put some pre tags in here so we
can see this a bit better.
4:04
Right before here we'll go ahead and do,
echo.
4:09
And then open up some tags for pre.
4:15
Close it out.
4:17
I'm gonna copy this line.
4:18
I'm gonna head down here and close out my
pre tag.
4:22
Let's go back and see if that makes it
looks a little nicer.
4:26
Much better.
4:31
So, looking at our result set here again,
we have a thousand results.
4:32
A lot of results.
4:35
We definitely would wanna paginate this in
a production environment, but
4:36
again, this is just for examples and not
to be put into production.
4:39
What do we have?
4:43
We have each one of the films it seems.
4:44
And a lot of information that looks
duplicate.
4:48
Okay, so the only difference between them
is the key.
4:50
So you see we have a film id and that's
equal to a string of one.
4:54
And then we have a numerically indexed
zero, so
4:59
the first index zero, with an id of one.
5:03
Double checking title.
5:07
Key of title, that's the academy dinosaur.
5:09
All right?
5:12
And then index one, which is a second key.
5:13
And that's the same, title as well.
5:17
So it looks like we have something indexed
by column name and
5:19
something indexed by a numeric index.
5:22
So let's go back to our PDO statement,
fetchAll.
5:25
Look at the manual, and the first optional
argument is the fetch style,
5:29
which takes another argument called fetch
argument.
5:35
Okay, so let's look down here at fetch
style.
5:38
So it says fetch_style controls the
content of the returned array as
5:43
documented in the Fetch documents.
5:47
So let's go to Fetch, see what that says.
5:49
Okay this is a result set, single row,
fetch_style parameters.
5:53
Okay so the default here, it says, is
returns an
5:59
array indexed by both column name and zero
indexed column number.
6:02
That's what we have.
6:08
That's our default.
6:09
But the option to do just the associative
array, is our first argument here.
6:10
Great, great.
So that's PDO fetch.
6:15
ASSOC or associative.
6:18
So it returns an array index by column
name as a return in your result set.
6:20
Let's do that.
6:25
So we wanna set
fetch_style to PDO::FETCH_ASSOC.
6:26
So I'm gonna copy this here and
6:30
I'm gonna pass that through in our code
here in our FetchAll statement.
6:32
Right here is our first argument.
6:37
Gonna paste in that class constant.
6:39
Hit Save.
6:42
Let's go back to our code and refresh.
6:43
Okay.
6:46
Still 1,000 results.
6:47
That's right.
That's exactly what we were looking for.
6:49
And now all of them are indexed by column
name.
6:52
So there's no miscellaneous zero through
whatever for the keys.
6:55
It's just an associative array for each
film, that's awesome.
6:59
So now we know that our result set is a
set of films indexed by a column name,
7:03
so we should be able to build out our code
a little bit.
7:09
So next we'll do that by providing some
links,
7:12
work with these results, and create a
little bit more of a website.
7:15
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