Simple SQL query selecting from table where email = email - php

I've got two php values called $email and $pass.
email - Name of row in MySQL database
password - Name of row in MYSQL database
I'm running a sql query to select from table member where email = $email and password =$pass.
I'm then running mysqli_query to see if a row exists, I'm not getting any results. Surely the echo would echo out the ID of where the info matches.
//Get the connection info.
global $connect;
$sql = "SELECT FROM members WHERE email='$email' AND password='pass'";
//Fetch the row and store the ID of this row.
$row = mysqli_query($connect, $sql);
$id = $row['userID'];
echo $id;

Besides the fact that this code is massively exposed to SQL injection.. you are querying the data but not fetching the results.
add the fetch command:
$data = mysqli_query($connect, $sql);
$row = mysqli_fetch_assoc($data);
$id = $row['userID'];

Related

Why is my mysqli_fetch_assoc not grabbing the row info so I can insert details into my table?

First off, I know about sql injection and that my code is not foolproof, prone to injection etc. Will be working on that next.
Now : from my Android app to my PHP file I submit a JSON array of phone numbers like :
[{"phone_number":"+12345678"},
{"phone_number":"+23456789"},
{"phone_number":"34567890"},
{"phone_number":"45678901"}
etc... etc...
These are contacts in my app user's phone. If these contacts are people who are also users of my app then I want to insert those numbers into my contacts table.
But I can't get it to work. mysqli_fetch_assoc isn't working correctly. I don't know why.
In my contacts table I have 3 columns - an auto increment, user_id and contact_id. The first two values are inserted correctly but the contact_id is always put in as '0', which is wrong.
Here is my code :
require('dbConnect.php');
//this is me, +567890123, my user_id in the user table
$user_id = '20';
//post all contacts in my phone as a JSON array
$json = $_POST['phonenumber'];
$array = json_decode($json);
foreach ($array as $value) {
$phonenumber = $value->phone_number;
$sql = "SELECT username FROM user WHERE username = '$phonenumber'";
$result = mysqli_query($con, $sql);
$num_rows = mysqli_num_rows($result);
if ($num_rows > 0) {
echo "phonenumber is " . $phonenumber . "<br>";
// we want to put $phonenumber in the contacts table, as one of +567890123 contacts
// In the user table get the associated rows of $phonenumber
while ($row = mysqli_fetch_assoc($result)) {
// get the associated user_id in that row, that's what we want to put into the contacts table
$contact_id = $row['user_id'];
$insert_into_contacts_command = "INSERT INTO contacts VALUES(NULL, '$user_id','$contact_id')";
$insert_into_contacts_table = mysqli_query($con, $insert_into_contacts_command);
}
} //if +353864677745 is NOT in the user table...
else {
echo 'not a match.';
}
}
$contact_id = $row['user_id'];
Here $contact_id will be null, because you are trying to access not existing field $row['user_id'] of the $row .
Actually there is only one field username in your results set, as you specified:
$sql = "SELECT username FROM user WHERE username = '$phonenumber'";
Try to change your query to this:
$sql = "SELECT user_id, username FROM user WHERE username = '$phonenumber'";
Your query selects the column username, not userid.
You haven't posted anything about the table user, so it's hard to suggest a new query, but I guess it's the following:
$stmt = mysqli_prepare($con, "SELECT userid FROM user WHERE username = ?");
$stmt->bind_param("s", $phonenumber);
$stmt->execute();
$stmt->bind_result($userid);
while ($stmt->fetch()) {
// Work with $userid
}
You'll note that this uses a prepared statement with a bound parameter. That way, your code is not prone to SQL injections.

Select an id in php script from a DB (Android)

I'm developing an app for android that uses a DB on a server.
I wrote some script php to create new rows in some tables and get all elements from a table (using JSON to exchange data between android and mysql).
Now I have a problem:
i need to select an id from a table and then use this to insert a row in anothere table that has this foreign key.
Well, when I try to select my id, i don't know why, but look like it doesn't work.
Here a simple example how I select this id:
//connect to DB...
$result = mysql_query (*SELECT id FROM 'table' WHERE name = $name );
$row = mysql_fetch_assoc($result);
$id = $row['id'];
When i use this to select an id, and put it in another query (always on the same connectio) nothing is stored.
if I force the value manually, and so in the same second query I put a number of a preesisting id, the insert works, so the problem is in this piece of code.
Hope someone could help me.
Thank you!
The code that you have put on the question, contains syntax errors.
- Remove * from the start of query
- put the query inside " "
- remove single quote ('table') from table name
Here is the modified code:
//connect to DB...
$result = mysql_query ("SELECT id FROM table WHERE name = $name" );
$row = mysql_fetch_assoc($result);
$id = $row['id'];
Also you should escape the parameter $name in query. And you should use mysqli or PDO instead of mysql extension.
try this:
$result = mysql_query (*SELECT id FROM 'table' WHERE name = $name );
$row = mysql_fetch_assoc($result);
while($row > 0){
$id = $row['id'];
}

PHP - Unable to retrieve data from the database

For some reason, the query when run through PHP will not return the results. I have tried both queries in the MySQL command line, and they work perfectly there. Here is the code (mysql_connect.php is working perfectly, to clarify).
<?php
error_reporting(-1);
// retrieve email from cookie
$email = $_COOKIE['email'];
// connect to mysql database
require('mysql_connect.php');
// get user_id by searching for the email it corresponds to
$id = mysqli_query($dbc,"SELECT user_id FROM users WHERE email=$email")or die('couldn\'t get id');
// get data by using the user_id in $id
$result = mysqli_query($dbc,"SELECT * FROM users WHERE user_id=$id")or die('couldn\'t get data');
//test if the query failed
if($result === FALSE) {
die(mysql_error());
echo("error");
}
// collect the array of results and print the ones required
while($row = mysql_fetch_array($result)) {
echo $row['first_name'];
}
?>
When I run the script, I get the message "could not get id", yet that query works in the MySQL command line and PHPMyAdmin.
Your code won't work for 2 reasons - $id will not magically turn into integer, but a mysqli result. And email is a string so it should be quoted.
But...
Why is all of that?
If you want to fetch all the data for user, for certain email, just make you second query fetch data by email and remove the first one:
SELECT * FROM users WHERE email='$email';
And don't forget to escape your input, because it's in cookie. Or, use prepared statements as suggested.
Your query is not valid, you should rewrite it with the following and make sure your you have mysqli_real_escape_string of the $email value before you put it into queries:
SELECT user_id FROM users WHERE email='$email'
Better approach is to rewrite your queries using MySQLi prepared statements:
Here how to get the $id value:
$stmt = mysqli_prepare($dbc, "SELECT user_id FROM users WHERE email = ?");
mysqli_stmt_bind_param($stmt, "s", $email);
mysqli_stmt_execute($stmt);
mysqli_stmt_bind_result($stmt, $id);
mysqli_stmt_fetch($stmt);
You wrote
mysqli_query($dbc,"SELECT user_id FROM users WHERE email=$email");
that is similar to
mysqli_query($dbc,"SELECT user_id FROM users WHERE email=example#example.com");
but it should be
mysqli_query($dbc,"SELECT user_id FROM users WHERE email='example#example.com'");
so you have to do this
mysqli_query($dbc,"SELECT user_id FROM users WHERE email='$email'");
or better
mysqli_query($dbc, 'SELECT user_id FROM users WHERE email=\'' . $email . '\'');
Beside this minor bug
You should be aware of SQL injection if someone changes the value of your cookie.

Reading from a database with PHP

I'm trying to pull some information from a database, and the connection is working, but for some reason it isn't recognizing my query, even though I confirmed the query in the database with SQL and had it "generate PHP code". The echo statement is coming up blank. It's a mySQL database. Thanks for your help.
$query = "SELECT `contact` FROM `contactinfo` WHERE member=\'Henry\'";
$contact = mysqli_query($db,$query);
echo $contact;
$contact contains MySQL result object you need to fetch data from this to use this in your application.
$query = "SELECT `contact` FROM `contactinfo` WHERE member = 'Henry'";
$contact = mysqli_query($db, $query);
while ($row = mysqli_fetch_row($contact)) {
echo $row[0]; // 0 to n indicates the Column(s) Selected in SELECT Query
}

show row data from a specific ID

I'm building a simple bug tracking tool.
You can create new projects, when you create a project you have to fill in a form, that form posts to project.class.php (which is this code)
$name = $_POST['name'];
$descr = $_POST['description'];
$leader = $_POST['leader'];
$email = $_POST['email'];
$sql="INSERT INTO projects (name, description, leader, email, registration_date)
VALUES ('$name', '$descr', '$leader', '$email', NOW())";
$result = mysql_real_escape_string($sql);
$result = mysql_query($sql);
if($result){
header('Location: ../projectpage.php?id='.mysql_insert_id());
}
else {
echo "There is something wrong. Try again later.";
}
mysql_close();
(It's not yet sql injection prove, far from complete...)
Eventually you get redirected to the unique project page, which is linked to the id that is stored in the MySQL db. I want to show the name of that project on the page, but it always shows the name of the first project in the database.
(here I select the data from the MySQL db.)
$query = 'SELECT CONCAT(name)
AS name FROM projects';
$result = mysql_real_escape_string($query);
$result = mysql_query ($query);
(here I show the name of the project on my page, but it's always the name of the first project in the MySQL db)
<?php
if ($row = mysql_fetch_array ($result))
echo '<h5>' . $row['name'] . '</h5>';
?>
How can I show the name of the right project? The one that is linked with the id?
Do I have the use WHERE .... ?
Yes, You have to use the WHERE to specify which project You want to get. I'm also not sure why are You using CONCAT function when You want to get only one project.
Other important thing is that You have to use mysql_real_escape_string() function on parameters before You put them in the query string. And use apropriate functions for specific type of data You receive.
So Your statement for getting the project should look like this:
SELECT name FROM projects WHERE id = ' . intval($_GET['id'])
Also when before You use the mysql_fetch_assoc() function, check if there are any records in the result with
if(mysql_num_rows($result) > 0)
{
$project = mysql_fetch_assoc($result);
/* $project['name'] */
}
try this
// first get the id, if from the url use $_GET['id']
$id = "2";
$query = "SELECT `name` FROM `projects` WHERE `id`='".intval($id). "'";
$result = mysql_query(mysql_real_escape_string($query));
use mysql_fetch_row, here you'll not have to loop through each record, just returns single row
// if you want to fetch single record from db
// then use mysql_fetch_row()
$row = mysql_fetch_row($result);
if($row) {
echo '<h5>'.$row[0].'</h5>';
}
$row[0] indicates the first field mentioned in your select query, here its name
The might be of assistance:
Your are currently assing a query string parameter projectpage.php?id=
When you access the page the sql must pick up and filter on the query string parameter like this:
$query = 'SELECT CONCAT(name) AS name FROM projects WHERE projectid ='. $_GET["id"];
$result = mysql_real_escape_string($query);
$result = mysql_query ($query);
Also maybe move mysql_insert_id() to right after assigning the result just to be safe.
$result = mysql_query($sql);
$insertId = mysql_insert_id();
Then when you assign it to the querystring just use the parameter and also the
header('Location: ../projectpage.php?id='.$insertId);

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