PHP Fetch row data from Mysql via ID - php

Question

I am new to php. I have the following code that auto fetches all the rows and columns from the db. I want to make the script to fetch a particular row using its ID column. for example: www.site.com/view.php?id=22
I am trying to get it work with the $_GET['link']; variable like this:
if (isset($_GET['id'])) {
$result = mysqli_query($connection,"SELECT * FROM $_GET['link']");
} else {
$result = mysqli_query($connection,"SELECT * FROM reservations");
}
But I am unable to get it work.
The complete code is as below:
<?php
$host = "localhost";
$user = "user";
$pass = "Pass1";
$db_name = "test";
//create connection
$connection = mysqli_connect($host, $user, $pass, $db_name);
//test if connection failed
if(mysqli_connect_errno()){
die("connection failed: "
. mysqli_connect_error()
. " (" . mysqli_connect_errno()
. ")");
}
//get results from database
$result = mysqli_query($connection,"SELECT * FROM reservations");
$all_property = array(); //declare an array for saving property
//showing property
echo '<table class="data-table" border="1">
<tr class="data-heading">'; //initialize table tag
while ($property = mysqli_fetch_field($result)) {
echo '<td>' . $property->name . '</td>'; //get field name for header
array_push($all_property, $property->name); //save those to array
}
echo '</tr>'; //end tr tag
//showing all data
while ($row = mysqli_fetch_array($result)) {
echo "<tr>";
foreach ($all_property as $item) {
echo '<td>' . $row[$item] . '</td>'; //get items using property value
}
echo '</tr>';
}
echo "</table>";
?>
Any help would be appreciated..

Answer 1

You can do this
Add
$query = 'SELECT * FROM reservations';
if (!empty($_GET['id']) and ($id = (int)$_GET['id']))
$query .= " WHERE id = {$id} LIMIT 1";
and change this
mysqli_query($connection,"SELECT * FROM reservations");
to this
$result = mysqli_query($connection, $query);
In the above code I added a bit of security so that if $_GET['id'] is not a valid integer it will revert to query where it fetches all the data. I added that because you should never put $_GET directly into your query.
Here is a your code I have modified it to your requirements
<?php
$host = "localhost";
$user = "user";
$pass = "Pass1";
$db_name = "test";
//create connection
$connection = mysqli_connect($host, $user, $pass, $db_name);
//test if connection failed
if(mysqli_connect_errno()){
die("connection failed: "
. mysqli_connect_error()
. " (" . mysqli_connect_errno()
. ")");
}
$query = 'SELECT * FROM reservations';
if (!empty($_GET['id']) and ($id = (int)$_GET['id']))
$query .= " WHERE id = {$id} LIMIT 1";
//get results from database
$result = mysqli_query($connection, $query);
$all_property = array(); //declare an array for saving property
//showing property
echo '<table class="data-table" border="1">
<tr class="data-heading">'; //initialize table tag
while ($property = mysqli_fetch_field($result)) {
echo '<td>' . $property->name . '</td>'; //get field name for header
array_push($all_property, $property->name); //save those to array
}
echo '</tr>'; //end tr tag
//showing all data
while ($row = mysqli_fetch_array($result)) {
echo "<tr>";
foreach ($all_property as $item) {
echo '<td>' . $row[$item] . '</td>'; //get items using property value
}
echo '</tr>';
}
echo "</table>";

Answer 2

if(isset($_GET['id'])) {
$id = $_GET['id'];
} else {
$id=NULL;
}
$sql = "SELECT * FROM reservations WHERE id = '".$id."'";
$result = mysqli_query($connection,$sql);
$row = mysqli_fetch_assoc($result);
if(mysqli_num_rows($result) == 1) {
dd($row);
} else {
echo "no records found with this id";
}
Hope this script meets your answer