No Database Selected Php - php

This is a somewhat simple task, I am trying to compare a username to that in the database. I am testing it out in a single php file before I do it properly. My code is below. Basically I have a user, which is in the database and I am checking if it is in there.
<?php
$db_connect = mysql_connect("127.0.0.1", "root", "anwesha01", "mis");
//Check if connection worked.
if(!$db_connect)
{
die("Unable to connect to database: " . mysql_error());
}
//For testing purposes only.
else
{
echo "Database connect success!";
}
$user = "alj001";
$query = "SELECT Username FROM `user` WHERE `Username` = '".$user."'";
//What is being passed through the database.
echo "<p><b>This is what is being queried:</b> " . $query;
//Result
if (mysql_query($query, $db_connect))
{
echo "<br> Query worked!";
}
else
{
echo "<p><b>MySQL error: </b><br>". mysql_error();
}
?>
The result I get is:
Database connect success!
This is what is being queried: SELECT Username FROM user WHERE Username = 'alj001'
MySQL error: No database selected
First I had my mysql_query without the $db_connect as it is above, but I put it in and I still get "no database selected".
Ive looked at the w3c schools for the mysql_query function, I believe I have done everything correctly. http://www.w3schools.com/php/func_mysql_query.asp

Because you haven't called mysql_select_db. Note that the 4th parameter to mysql_connect is not what you think it is.
That said, you really should be using PDO or mysqli, not the plain mysql_ functions, since they're deprecated.

Related

How do I obtain data through a MySQL Database using GET in PHP?

I've tried the solutions in this question, however mysql has been depricated for mysqli. Even with these changes it still doesn't return the information, instead returns an error, with nothing else (Nothing is heard from mysqli)
What i'm trying to do is kind of similar to the question linked, however it would look like this in the url: example.com?view-work=A01 It would search for A01 in the database, then return the Name, description, an image URL and date it was made live.
This is the code that i've been able to make using the answers from the question:
<?php
//Establishing a connection to the Artwork Database
mysqli_connect('localhost', 'dbuser', 'dbpassword');
mysqli_select_db('db');
$artworkidentifier = $_GET["view_work"];
//Returning the result, if there is one
$artworkidentifier = mysqli_real_escape_string($artworkidentifier);
$sql = "SELECT * FROM ArtDB WHERE art_refcode = '$artworkidentifier'";
$result = mysqli_query($sql);
if (!$result) {
echo "Something's gone wrong! ".mysqli_error();
}
$data = mysqli_fetch_assoc($result);
echo $data["Artwork_Name"];
echo $data["Artwork_Description"];
echo $data["Artwork_URL"];
echo $data["DateUploaded"];
?>
Seems like the cause of these errors was my own incompetence, also probably the fact I'm kind of new to PHP and MySQL in general. I learnt that I needed to reference my connection in some of the commands for them to successfuly process after adding the debug exception mentioned in the OP's comments.
As someone also pointed out, Yes this code is still vulnerable to other types of SQL injection, I'll be addressing these before the final version of the code goes live.
Fixed Code:
<?php
//Establishing a connection to the Artwork Database
$link = mysqli_connect('localhost', 'dbusr', 'dbpasswd', 'db');
//Exeptional Debugging
ini_set('display_errors', 1);
ini_set('log_errors', 1);
error_reporting(E_ALL);
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
if (!$link) {
echo "Error: Unable to connect to MySQL!";
echo "Error No.".mysqli_connect_errno();
echo "Error in question: ".mysqli_connect_error();
exit;
}
$artworkidentifier = $_GET["view_work"];
//Returning the result, if there is one
$artworkidentifier = mysqli_escape_string($link, $artworkidentifier);
$sql = "SELECT * FROM ArtDB WHERE art_refcode = '$artworkidentifier'";
$result = mysqli_query($link, $sql);
if (!$result) {
echo "Something's gone wrong!"; //This line will be changed later to sound more professional
}
$data = mysqli_fetch_assoc($result);
echo $data["Artwork_Name"];
echo $data["Artwork_Description"];
echo $data["Artwork_URL"];
echo $data["DateUploaded"];
?>

Can't fetch data from database table.... 500 error

I have tried a ton of different versions of this code, from tons of different websites. I am entirely confused why this isn't working. Even copy and pasted code wont work. I am fairly new to PHP and MySQL, but have done a decent amount of HTML, CSS, and JS so I am not super new to code in general, but I am still a beginner
Here is what I have. I am trying to fetch data from a database to compare it to user entered data from the last page (essentially a login thing). I haven't even gotten to the comparison part yet because I can't fetch information, all I am getting is a 500 error code in chrome's debug window. I am completely clueless on this because everything I have read says this should be completely fine.
I'm completely worn out from this, it's been frustrating me to no end. Hopefully someone here can help. For the record, it connects just fine, its the minute I try to use the $sql variable that everything falls apart. I'm doing this on Godaddy hosting, if that means anything.
<?php
$servername = "localhost";
$username = "joemama198";
$pass = "Password";
$dbname = "EmployeeTimesheet";
// Create connection
$conn = mysqli_conect($servername, $username, $pass, $dbname);
// Check connection
if (mysqli_connect_errno) {
echo "Failed to connect to MySQL: " . mysqi_connect_error();
}
$sql = 'SELECT Name FROM Employee List';
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) > 0) {
while($row = mysqli_fetch_assoc($result)) {
echo "Name: " . $row["Name"]. "<br>";
}
} else {
echo "0 results";
}
mysqli_close($conn);
?>
There be trouble here:
// Create connection
$conn = mysqli_conect($servername, $username, $pass, $dbname);
// Check connection
if (mysqli_connect_errno) {
echo "Failed to connect to MySQL: " . mysqi_connect_error();
}
There are three problems here:
mysqli_conect() instead of mysqli_connect() (note the double n in connect)
mysqli_connect_errno should be a function: mysqli_connect_errno()
mysqi_connect_error() instead of mysqli_connect_error() (note the l in mysqli)
The reason you're getting a 500 error is that you do not have debugging enabled. Please add the following to the very top of your script:
ini_set('display_errors', 'on');
error_reporting(E_ALL);
That should prevent a not-so-useful 500 error from appearing, and should instead show the actual reason for any other errors.
There might be a problem here:
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) > 0) {
If the query fails, $result will be false and you will get an error on the mysqli_num_rows() call. You should add a check between there:
$result = mysqli_query($conn, $sql);
if (!$result) {
die('Query failed because: ' . mysqli_error($conn));
}
if (mysqli_num_rows($result) > 0) {
The name of your database table in your select statement has a space in it. If that is intended try:
$sql = 'SELECT Name FROM `Employee List`';
i think you left blank space in your query.
$sql = 'SELECT Name FROM Employee List';
change to
$sql = "SELECT `Name` FROM `EmployeeList`";

PHP mysqli_query won't execute

I'm trying to write my first basic PHP RESTful API - I managed to get it working on my local machine using MAMP. But when I uploaded to hosting server, it doesn't want to work.
Code below - I've added some ECHO's in there to make sure things are working along the way. It seems like we're all good up until the $result=mysqli_query.
<?php
//header('Content-type:application/json');
// Connect to db
$con = mysqli_connect("HOSTNAME","USER","PASSWORD","DATABASE");
echo "Database: ";
// Check connection
if ($con->connect_error) {
die("Connection failed: " . $con->connect_error);
}
echo "Connected successfully";
echo "<br><br>";
// Get value from url
$bid = $_GET['bid'];
echo "BID: ";
echo $bid;
echo "<br><br>";
// Define Query
$sql = "SELECT id, bandname, members, bio, songlist FROM bands WHERE id='$bid'";
echo "SQL Query: ";
echo $sql;
echo "<br><br>";
// Run Query
$result = mysqli_query($con, $sql);
echo "Result: ";
print_r($result);
echo "<br><br>";
// Put Query result into array
$result_array = mysqli_fetch_array($result, MYSQLI_ASSOC);
echo "Result Array: ";
print_r($result_array);
echo "<br><br>";
// Encode array as JSON and output
echo "JSON: ";
echo json_encode($result_array);
?>
The url I'm entering is http://bandsly.com/api.php?bid=1 and this is the output I'm getting in the browser...
Database: Connected successfully
BID: 1
SQL Query: SELECT id, bandname, members, bio, songlist FROM bands WHERE id='1'
Result:
Result Array:
JSON: null
When I manually run the query SELECT id, bandname, members, bio, songlist FROM bands WHERE id='1' in the database (PHPmyadmin), it works fine and I get 1 row returned with the correct values.
The manual db query result:
(http://i.stack.imgur.com/d3ZPJ.png)
Any help would be most appreciated!!
*****EDIT*****
OK, i think i found the issue... My "successfully Connected" wasn't written correctly, and always came back looking good. It looks like after fixing that, i have db connection issues.
I'm going to go look up the db connection settings and try and fix that.
Thanks all for your help!
Your code seems to be ok on my localsystem http://www.awesomescreenshot.com/image/494275/c6c255cd6924d07196076b32489489de. There should be a connection problem . so you can do some try to check connection like
check the details in
// Connect to db
$con = mysqli_connect("HOSTNAME","USER","PASSWORD","DATABASE");
and then you can try to ping database
/* check connection */
if ($con->connect_errno) {
printf("Connect failed: %s\n", $con->connect_error);
exit();
}
/* check if server is alive */
if ($con->ping()) {
printf ("Our connection is ok!\n");
} else {
printf ("Error: %s\n", $con->error);
}
Your all code is correct, I have tested in my local just change your
HOSTNAME like "localhost", USER like "root", PASSWORD like "your password", DATABASE like "YOUR DATABASE NAME".
$con = mysqli_connect("HOSTNAME","USER","PASSWORD","DATABASE");
please, visit http://php.net/manual/en/function.mysqli-connect.php

Outputting contents of database mysqli

Hi I know this is a little general but its something I cant seem to work out by reading online.
Im trying to connnect to a database using php / mysqli using a wamp server and a database which is local host on php admin.
No matter what I try i keep getting the error Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given when i try to output the contents of the database.
the code im using is:
if (isset($_POST["submit"]))
{
$con = mysqli_connect("localhost");
if ($con == true)
{
echo "Database connection established";
}
else
{
die("Unable to connect to database");
}
$result = mysqli_query($con,"SELECT *");
while($row = mysqli_fetch_array($result))
{
echo $row['login'];
}
}
I will be good if you have a look at the standard mysqli_connect here
I will dont seem to see where you have selected any data base before attempting to dump it contents.
<?php
//set up basic connection :
$con = mysqli_connect("host","user","passw","db") or die("Error " . mysqli_error($con));
?>
Following this basic standard will also help you know where prob is.
you have to select from table . or mysqli dont know what table are you selecting from.
change this
$result = mysqli_query($con,"SELECT *");
to
$result = mysqli_query($con,"SELECT * FROM table_name ");
table_name is the name of your table
and your connection is tottally wrong.
use this
$con = mysqli_connect("hostname","username","password","database_name");
you have to learn here how to connect and use mysqli

Error:NO database is selected

I tried it connection to database connection to database is successful but when i try to match user information with database it gives me a error NO database is selected
i tried it connecting to database using different method but nothing worked
<?php
//CREATING CONNECTION TO DATABASE
$con= new mysqli("localhost", "****", "***", "*****");
$con->select_db("lel_server_user_db_secured");
if(mysqli_connect_errno())
{
echo "Problem With connection to database Please contact administrator regarding this error";
}
/* RETURNS NAME OF DEFAULT DATABASE
if ($result = $con->query("SELECT DATABASE()")) {
$row = $result->fetch_row();
printf("Default database is %s.\n", $row[0]);
$result->close();
}
*/
/*
$host="localhost";
$db_user="sky.xpert";
$db_pass="havefun344";
$database="lel_server_user_db_secured";
mysqli_connect($host,$db_user,$db_pass,$database) or die ("Failed to connect");
mysqli_select_db($database) ;
*/
session_start();
//GATHERING DATA FROM USER FORM
$email=$_POST["login"];
$pass=$_POST["pwd"];
//COMMANDING WHERE TO FIND MATCH FOR LGOIN INFORMATION
$veryfy="SELECT * FROM users WHERE Email='$email' Password='$pass'";
$query=mysql_query($veryfy) or die ( mysql_error() );
$match=0;
$match=mysql_num_rows($query);
//IF MATCH FOUND THEN SETTING SESSION AND REDIRECTING IT TO LOGGED PAGE
if($match==1)
{
$_SESSION['loggedin'] = "true";
header ("Location: logged.php"); //REDIRECTING USER TO ITS HOMEPAGE
}
else //IF MATCH NOT FOUND THEN REDIRECTING IT BACK TO LOGIN PAGE
{
$_SESSION['loggedin'] = "false";
header ("Location: index.php");
}
//PERSONAL COMMENTS OR DETIALED COMMENTS
//PROBLEM WITH THIS SCRIPT GIVING OUTPUT ON LOGIN "NO DATABASE SELECTED"
//REFRENCE from http://www.dreamincode.net/forums/topic/52783-basic-login-script-with-php/
?>
You are initializing a connection to your database with mysqli. Then you try to do queries with mysql. Obviously, there is no connection with the database made through that library, and therefore it fails with an error. Change mysql_query to mysqli_query.
General note
Your current code is vulnerable to sql injection attacks, because you do not sanitize the input from the user before putting it in a query. Consider using prepared queries.
The database lel_server_user_db_secured may be not exist.
Content to your mysql:
mysql -hlocalhost -uusername -p
then input your password. After login, type command:
show databases;
check if lel_server_user_db_secured is in the result.
update1*
change the code below:
$veryfy="SELECT * FROM users WHERE Email='$email' Password='$pass'";
$query=mysql_query($veryfy) or die ( mysql_error() );
$match=0;
$match=mysql_num_rows($query);
to:
$veryfy="SELECT * FROM users WHERE Email='$email' Password='$pass'";
$result = mysqli_query($con, $veryfy) or die ( mysqli_connect_errno() );
$match=0;
$match=mysqli_num_rows($result);
var_dump($match);
In the first half of your program you have used mysqli and in the latter half mysql. Either use mysqli or mysql. I would recommend using mysqli in your entire program so that you are not vulnerable to SQL injection
you can simply do it by
$mysqli = new mysqli("localhost", "user", "password", "database");
if ($mysqli->connect_errno) {
echo "Failed to connect to MySQL: (" . $mysqli->connect_errno . ") " . $mysqli->connect_error;
}
there is no need to do $con->select_db("lel_server_user_db_secured"); again
and using mysqli isnt mean your code is safe ... your code is still vulnerable to SQL injection Use prepared statement instead or atleast mysqli_real_escape_string
You need to escape all request properly
and its possible that your database isnt exist so check that its exist first
AND you are mixing tow different API
you can not use MySQLi functions with MySQL_* function

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