Is it possible to nest mysqli commands

Question

Using the php mysql functions, if I have a query that I know will only return one row from the data table I nest the functions like this:

$myVariable = mysql_fetch_assoc(mysql_query("SOME QUERY"));

Using the mysqli functions I have to have to use two lines of code:

$query = $db->query("SOME QUERY");
$myVariable = $query->fetch_assoc();

Is it possible to condense the two lines into one as I do using the older mysql functions?

You cloud simply use `mysqli_query` etc. (not beautiful but wokring). Maybe (not tested) you could use `$db->query("...")->fetch_assoc();` — Le_Morri, Jun 24 '13 at 10:57
@Jimbo yes, I had tried myself, but after a few variations that didn't work I thought I'd ask people who may have done it before. I've only started looking into mysqli today. — AndrewDFrazier, Jun 24 '13 at 11:00
Not sure why this was closed as "not constructive". Seems a valid question to me. Voted to reopen. — MrCode, Jun 24 '13 at 11:24

score 1 · Answer 1 · edited May 23 '17 at 12:05

1

You can chain them:

$myVariable = $db->query("SOME QUERY")->fetch_assoc();

Although both that and your intial mysql_ usage are prone to errors. Neither will handle a failed query particularly nicely.

edited May 23 '17 at 12:05

Community

answered Jun 24 '13 at 10:58

bcmcfc

MrCode · Accepted Answer · 2013-06-24T11:22:26.703

1

Yes you can do it but I wouldn't recommend it:

$myVariable = $db->query("SOME QUERY")->fetch_assoc();

It's a bad idea because you don't get the opportunity to do any error handling. For example:

$myVariable = array();

$result = $db->query("SOME QUERY");
if($result && $result->num_rows == 1)
{
    $myVariable = $result->fetch_assoc();
}

If you nest or chain the calls, you might run into unhandled fatal errors because query() will return false if there was a MySQL error.

If you're looking to tidy up your code or reduce it, you could extend the MySQLi class and add your own method to fetch a single row.

edited Jun 24 '13 at 11:22

answered Jun 24 '13 at 11:00

MrCode

Thanks, chaining was what I was looking for, as also mentioned by @Le_Morri. As I said, I use it when I know that there is only one record to be returned. – AndrewDFrazier Jun 25 '13 at 10:24

score -1 · Answer 3 · answered Jun 24 '13 at 11:05

As a matter of fact, you should not have to condense the two lines into one using older mysql functions, and shouldn't do it with new ones.

When a programmer needs to condense something, they write a function. So you have to.

So, what it have to be

$myVariable = my_function("SOME QUERY");

As you can see,

it is shorter and more readable than all these nested/chained/entangled constructs
it has error handling, profiling logging and many more
if you were using a function already, you won't even had to rewrite your existing code.

3 Answers3