mysqli_query problem

[AlexC]

As the query works fine in phpMyAdmin or MySQL workbench, I am assuming at present it is a php problem. I have the following code being used to uniquely identify a person from a form entry,

 

 

if (mysqli_connect_errno($condb))

{

echo 'Failed to connect to MySQL: ' . mysqli_connect_error();

}

else {echo 'connected';} //****debug 1

 

$firstname = preg_replace('/[^a-zA-Zs]/', '', $_POST['idfirstname'] );

$lastname = preg_replace('/[^a-zA-Zs]/', '', $_POST['idlastname'] );

$streetno = preg_replace('/[^0-9s]/', '', $_POST['idhouseno'] );

$telephone = preg_replace('/[^0-9s]/', '', $_POST['idtelephone'] );

 

// echo '<br>'.$firstname.', '.$lastname.', '.$streetno.', '.$telephone; //****debug 2

 

$query="SELECT .....;";

echo '<br><b>Query for user id:</b> <br>'.$query; //****debug 3

$result = mysqli_query($condb,$query);

$count = mysqli_num_rows($result);

echo '<br><b> row count:</b>'.$count.' - result: '.$result. '!'; //****debug 4

// --------------------------------------------------------------------------------------------------------------

// Check for unique data

/* if($count == 1) {

// unique ID successfull

while($row = mysqli_fetch_array($resultA))

{ ......

 

Code was working fine this morning and I was refining the code further on and adding other extraction options in new pages based on having a unique identification. However it has suddenly stopped working. Other parts of the site, not relying on this identification are working fine. Debug point 1 comes up fine as 'connected', the data at debug 2 is fine and if I cut and paste the query output in the browser from debug point 3 into phpMyAdmin or mySQL workbench, no problems, I get the results expected. However debug point 4 does not materialise. If I comment out the line $result = mysqli_query($condb,$query); debug 4 comes up, but obviously not with any results. I'm using Aptana workbench and that is not flagging any syntax errors. I have tried rewriting the line and cut and pasted a similar mysqli_query line from other pages where it is working in case a funny character had got into the code, but to no effect. As I have lots of other similar code instances still working fine, this is causing some frustration. Any ideas on what I am hoping is an obvious error that I just can't see, very much appreciated.

 

 

 

 

[niche]

Add mysqli_error() and let us know what the error message is if any.

 

http://www.w3schools.com/php/func_mysqli_error.asp

[AlexC]

Tried adding mysqli_error() and could not get any errors reported. I did add some code to simulate a successful query and the other three queries in the code worked fine. So I tried pasting in one of the $result = mysqli_query($dbAcon,$query) statements that worked for the other queries with no progress. The query causing the problem did have a join in it, but as I said, had been working fine. I was going to split the query to take out the join for other reasons, so I thought I'd try that as I was planning to run a demo on Tuesday and it is now working. I then did a quick survey of my other pages and found that the only places where I use joins I have created views in the database first. That's the only difference I can see. Although why it should work and then not work.... So I have a solution, but not a satisfactory reason for the failure.

 

many thanks for answering.

[birbal]

you should check if query is successfully executing or not. to do so you need to use mysqli_error() with mysql_query() too as mentioned by niche. If your query has external unescaped input, it could break the query.

[AlexC]

That's part of the problem - I'm not seeing any error returns at all. I see one echo, with the sqli_error, after the problem query statement and that's it. As far as I can see there is still a lot of valid HTML output that should come out on further echoes but if you view the source code in the browser there is just nothing else after the sqli_error echo, not even the closing Body and HTML tags.

[justsomeguy]

It sounds like there's a fatal error. Make sure you're seeing all error messages from PHP, add this to the top:

 

ini_set('display_errors', 1);

error_reporting(E_ALL);

[AlexC]

Thanks, that looks like a very useful tip.