PHP MySQL - Function - php

Question

i wrote a PHP Function but it does nothing at a specific point.. im new to php and my english is bad, sorry for that.
<?php
function SQLwriteRecent($id, $title, $link) {
$con=mysqli_connect("localhost","","","");
// Check connection
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$count = mysqli_query($con,"SELECT count FROM recent WHERE sc_stream='$id'");
if(!isset($count)) {
try {
mysqli_query($con,"INSERT INTO recent (title, link, sc_stream, count) VALUES ('$title', '$link', '$id',$count)");
mysqli_close($con);
return 1;
} catch(Exception $e) {
return 0;
}
} else {
try {
// ------ SHOW HERE!!!! ------------ //
mysqli_query($con,"UPDATE recent SET count=$count WHERE sc_stream='$id'");
mysqli_close($con);
return 2;
} catch(Exception $e) {
return 0;
}
}
}
?>
the code runs every time until a specific point (i marked it in the code with // ------ SHOW HERE!!!! ------------ //)
in the sql table, currently there is no entry. so i should create a new row
whats wrong with that code?! :(

Answer 1

Your script wont insert a new row, because you have defined $count, it is a mysqli_result object. You have to check if there is a row, something you could do like this;
Instead of
if(!isset($count))
use
if(mysqli_num_rows($count) == 0)

Answer 2

Some explanation:
You have this in your code:
if(!isset($count)) {
This checks that your variable has been set, nor is empty, false, or 0. This condition ALWAYS return true because the variable is setted in line before, use mysqli_nuw_rows instead

Answer 3

Combining what other people have said, and looking at the logic of what you're doing, it looks like you have a few fundamental issues:
I've tweaked some variable names to make it clearer what you're getting an peppered the code with comments that describe the issues.
I've ignored the SQL injection issues.
<?php
function SQLwriteRecent($id, $title, $link) {
$con=mysqli_connect("localhost","","","");
// Check connection
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$countQuery = mysqli_query($con,"SELECT count FROM recent WHERE sc_stream='$id'");
$numberOfRowsReturnedByQuery = mysqli_num_rows($count);
if ( $numberOfRowsReturnedByQuery > 0 ) {
$valueOfCountInQuery = $countQuery [0]['count'];
}
if( $numberOfRowsReturnedByQuery == 0) {
try {
// In this situation it looks like you want to set up a value in "recent" - I.E. you didn't have a record.
// But think about it for a second - if you had no record in "recent" then how could "$valueOfCountInQuery" possibly be set?
mysqli_query($con,"INSERT INTO recent (title, link, sc_stream, count) VALUES ('$title', '$link', '$id',$valueOfCountInQuery )"); // makes no sense to use "$valueOfCountInQuery" - maybe you mean "0" (zero)
mysqli_close($con);
return 1;
} catch(Exception $e) {
return 0;
}
} else {
try {
// In this situation it looks like you want to update the value in "recent" - I.E. you DID have a record and you want to change it.
// But think about it for a second - the value of "$valueOfCountInQuery" is the value that you got from "count" on "recent". You are setting it to the same value that's already in there!
// ------ SHOW HERE!!!! ------------ //
mysqli_query($con,"UPDATE recent SET count=$valueOfCountInQuery WHERE sc_stream='$id'"); // redundant
mysqli_close($con);
return 2;
} catch(Exception $e) {
return 0;
}
}
}
?>

Answer 4

You did a mistake here, query returns array
try this
mysqli_query($con,"UPDATE recent SET count=$count[0]['count'] WHERE sc_stream='$id'");

Answer 5

You have set:
count=$count
but
$count = mysqli_query($con,"SELECT count FROM recent WHERE sc_stream='$id'");
Specify a proper value for count not a resource

Answer 6

to retrieve the actual result of the query you have to do something like
if ( $result = $con->query($sql)){ //perform the query
if ($result->num_rows == 1){
if ($row = $result->fetch_assoc()){
$count = $row['count'];
}
else{
echo "couldn't fetch result row";
}
else {
echo "expected one result row, got ".$result->num_rows;
}
}
else {
echo "query failed:".$sql;
echo $con->errno.' '.$con->error;
}
// if you have more than one result row
if ( $result = $con->query($sql))
while ($row = $result->fetch_assoc()){ //loop through the result(s)
$count = $row['count']
}
// procedural style
if ( $result = mysqli_query($con,$sql))
while($row = mysqli_fetch_assoc($result)){