Why can't I connect to my psql db? - php

So I am trying to link my page a.php to my psql db.
Here's DBConnection.class.php:
<?php
class DBConnection
{
var $conn
function DBConnection();
{
$this->conn = pg_connect("host='localhost' port='5432' dbname='tester' user='postgres' password='password'") or die("unable to connect");
}
}
?>
and here's a.php
<?php
include ("DBConnection.class.php");
$DBConnection = new DBConnection();
?>
It keeps telling me I have an error on line seven of DBConnection: Fatal error: Non-abstract method DBConnection::DBConnection() must contain body in C:\wamp\www\DBConnection.class.php on line 7
I'm not entirely sure what I do as far as fixing this problem

Open php.ini
Find ;extension=php_pgsql.dll and remove the initial semi colon
Find ;extension=php_pdo_pgsql.dll and remove the initial semi colon
Save the file
Restart apache
remove the
;
from end of function name
class DBConnection
{
var $conn
function DBConnection()
{
$this->conn = pg_connect("host='localhost' port='5432' dbname='tester' user='postgres' password='password'") or die("unable to connect");
}
}
?>

Related

PHP 7.2 - Include file cannot access another include file

I am having an issue with an include file accessing another include file (my db connection)
I have a site with the following layout ::
root/conn.php :: db connection file
root/site/file1.php :: regular page
root/site/include/func.inc :: file with functions in it
Each file is listed below with appropriate code...
conn.php ::
<?php
$host = 'localhost';
$db = 'mydb';
$user = 'myuser';
$pass = 'mypass';
$charset = 'utf8mb4';
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
try {
$conn = new mysqli($host, $user, $pass, $db);
$conn->set_charset($charset);
} catch (\mysqli_sql_exception $e) {
throw new \mysqli_sql_exception($e->getMessage(), $e->getCode());
}
unset($host, $db, $user, $pass, $charset);
?>
file1.php ::
include_once ("{$_SERVER['DOCUMENT_ROOT']}/conn.php");
include_once ("{$_SERVER['DOCUMENT_ROOT']}/site/include/func.inc");
{ code that calls functions in func.php }
func.inc ::
include_once ("{$_SERVER['DOCUMENT_ROOT']}/conn.php");
{ various functions }
When I browse to /file1.php, I get the following error ::
PHP Notice: Undefined variable: conn in C:\inetpub\root\site\include\func.inc on line 231
PHP Fatal error: Uncaught Error: Call to a member function prepare() on null in C:\inetpub\root\site\include\func.inc:231
my func.inc file cannot seem to find the conn.php file. I have also tried removing the include function from func.inc. There are other files in the /include folder that can access the conn.php file with the same include function.
The issue relates to something called the variable scope (https://www.php.net/manual/en/language.variables.scope.php)
==> Please read that to get detailed information
The second example describes your problem
func.inc
<?php
include_once ("{$_SERVER['DOCUMENT_ROOT']}/conn.php");
// to illustrate the issue, the include can be simplified to
// $conn = "something"; // => global scope variable
function myFunc(){
echo $conn; //no output - $conn exists ONLY in the local scope --> not available inside thisfunction
}
Solution 1:
func.inc
<?php
function myFunc($conn){
echo $conn; //outputs $conn
}
file1.php
<?php
include_once ("{$_SERVER['DOCUMENT_ROOT']}/conn.php");
include_once ("{$_SERVER['DOCUMENT_ROOT']}/site/include/func.inc");
//call function and pass the $conn, it's available here in the global scope
myFunc($conn);
Solution 2
but keep in mind global is considered as bad practice
func.inc
<?php
include_once ("{$_SERVER['DOCUMENT_ROOT']}/conn.php");
function myFunc(){
global $conn; //$conn is declared global in the local scope of this function
echo $conn; //outputs $conn from conn.php if you call myFunc from anywhere
}

How to fix Fatal error: Cannot redeclare connectdb()

I am new for PHP and MYSQL. I have tried some learnings using xampp. when I try to connect database with the script it shows below error.. this showing on index.php
Fatal error: Cannot redeclare connectdb() (previously declared in
C:\xampp1\htdocs\core.php:18) in C:\xampp1\htdocs\core.php on line 24
I have a search on google and try to fix this. but it's not worked...
core.php line 18th to 24 th codes as follows.
function connectdb()
{
global $dbname, $dbuser, $dbhost, $dbpass;`
$conms = #mysql_connect($dbhost,$dbuser,$dbpass); //connect mysql`
if(!$conms) return false;`
$condb = #mysql_select_db($dbname);`
if(!$condb) return false;`
return true;`
}
config.php codes as follows
$dbname = "aw"; //change to your mysql database name
$dbhost = "localhost"; //database host name
$dbuser = "sam";
$dbpass = "1234";
$max_buds=100; //maximum number of buds
$topic_af = 120; //topic antiflood
$post_af = 45; //post antiflood
$onver = true; //isonline versoion
$timeadjust = (0 * 60 * 60); // 4 hours
putenv("TZ=Africa/Johannesburg");
It's called "include guard":
if(!function_exists('connectdb')) {
function connectdb() {
}
}
I think the issue that connectdb function already loaded.
Try use include_once instead of include.
example:
include_once 'Functions.php';
The include_once statement includes and evaluates the specified file during the execution of the script. This is a behavior similar to the include statement, with the only difference being that if the code from a file has already been included, it will not be included again, and include_once returns TRUE. As the name suggests, the file will be included just once.
https://www.php.net/manual/en/function.include-once.php
Try replacing your connectdb function with the following code:
if (!function_exists('connectdb')) {
function connectdb()
{
global $dbname, $dbuser, $dbhost, $dbpass;
$conms = #mysql_connect($dbhost,$dbuser,$dbpass); //connect mysql
if (!$conms) return false;
$condb = #mysql_select_db($dbname);
if (!$condb) return false;
return true;
}
}
It will only create the function if it does not exist.

undefined constant DB_SERVER - assumed 'DB_SERVER'

I have installed WAMP server on my local machine and I have written php script to insert record into the database, but I'm getting the following error-
Notice: Use of undefined constant DB_SERVER - assumed 'DB_SERVER' in C:\wamp\www\test_services\db_connect.php on line 32
following is my db_config code
<?php 
define('DB_USER', "root"); // db user
define('DB_PASSWORD', ""); // db password
define('DB_DATABASE', "test_db"); // database name
define('DB_SERVER', "localhost"); // db server
?>
Here is my **db_connect.php code**
<?php
/**
* A class file to connect to database
*/
class DB_CONNECT
{
// constructor
function __construct()
{
// connecting to database
$this->connect();
}
// destructor
function __destruct()
{
// closing db connection
$this->close();
}
/**
* Function to connect with database
*/
function connect()
{
// import database connection variables
require_once __DIR__ . '/db_config.php';
// Connecting to mysql database
$con = mysql_connect(DB_SERVER, DB_USER, DB_PASSWORD) or die(mysql_error());
// Selecing database
$db = mysql_select_db(DB_DATABASE) or die(mysql_error()) or die(mysql_error());
// returing connection cursor
return $con;
}
/**
* Function to close db connection
*/
function close()
{
// closing db connection
mysql_close();
}
}
?>
Please help.. Thank you..!
I don't think you are showing the correct file. The problem is in db_connect.php. It is very likely that that file does not include db_config.php, i.e:
require_once 'path/to/db_config.php';
Edit: Does db_config.php actually live in the same directory as db_connect.php? Your code suggests that it does, which may be incorrect?
Edit: What happens if you put $var = 'hello' in db_config.php, and then print $var in db_connect.php after you include it, do you see 'hello'? Just to clarify you are connecting with the file..

Trouble connecting to MySQL database using PHP

I have a 3 file:
class.database.php
config.php
test.php
In class.database.php i using:
<?php
class Database {
private $db_connect;
function __construct($config) {
$this->connect($config);
}
function connect($config) {
$this->db_connect = #mysql_connect($config['hostname'], $config['dbuser'], $config['dbpass']) or die("Can't connect to mysql server");
#mysql_select_db($config['dbname'], $this->db_connect) or die("Can't select database mysql server");
$this->query('set names utf8');
}
function disconnect() {
mysql_close($this->db_connect);
}
}
?>
in config.php i using:
<?php
include_once 'class.database.php';
$config['hostname'] = 'localhost';
$config['dbuser'] = 'root';
$config['dbpass'] = '';
$config['dbname'] = 'test';
$db = new Database($config);
?>
And test.php i using:
<?php
include 'config.php';
include 'class.database.php';
when to run test.php in wampserver is host alert error is Fatal error: Cannot redeclare class Database in class.database.php on line 2
How to fix it ?
You're includeing the class.database.php file twice, which gives this error. Use include_once for it always, not include.

PHP function for mysqli connection gives error

Newer to creating php functions and mysql. I have function to connect to a database db_conect_nm(). This is in file db_fns.php, and contains the user and password to connect to my db. I created this to have a more secure db connection. I had it in a directory outside of public_html, and got error PHP Warning: mysqli::mysqli() [<a href='mysqli.mysqli'>mysqli.mysqli</a>]: (28000/1045): Access denied for user 'negoti7'#'localhost' (using password: NO) ...
Looking for solutions, I saw comments which indicated that perhaps this db user did not have permission from root, so I put it in a directory in public_html, same directory as program where it is being called. I still get the same error.
I have tested the connection without being a function, and it works. What is wrong, and why is this not working as a function? I really want to put this somewhere other than in the code directly and make it more secure.
db_fns.php content
<?php
//Database server
$host= 'localhost';
$nm_name= 'myname_databasename'; //sanitized data
$nm_user= 'myname_dbusername';
$nm_pword= 'password';
// db connect to nm database
function db_connect_nm()
{
$nm_connect = new mysqli($host, $nm_user, $nm_pword, $nm_name);
if (!$nm_connect)
throw new Exception('Could not connect to NM database currently');
else
return $nm_connect;
}
?>
I call it from nm_functions.php, db_fns.php is included there.
nm_functions.php
<?php require_once('sanitizedpathto/db_fns.php');
......some code
$conn_nm = db_connect_nm();
$result_sub = $conn_nm->query("select * from subscribers where uname='$username'");
.... more code
?>
Any ideas?
Thanks
Could it be the scope of the variables? Have you tried defining the variables inside the function to test?
Like this:
<?php
// db connect to nm database
function db_connect_nm()
{
//Database server
$host= 'localhost';
$nm_name= 'myname_databasename'; //sanitized data
$nm_user= 'myname_dbusername';
$nm_pword= 'password';
$nm_connect = new mysqli($host, $nm_user, $nm_pword, $nm_name);
if (!$nm_connect)
throw new Exception('Could not connect to NM database currently');
else
return $nm_connect;
}
?>
You are :
first, declaring some variables, outside of any functions
then, trying to use those variables from inside a function.
Variables declared outside of a function are not, by default, visible from inside that function.
About that, you should read the Variable scope section of the manual.
Two possible solutions :
Use the global keyword, to import those variables into your function -- making them visible
Or define constants, instead of variables -- which makes sense, for configuration values.
In the first case, your function would look like this :
// db connect to nm database
function db_connect_nm()
{
// Make these outside variables visible from inside the function
global $host, $nm_user, $nm_pword, $nm_name;
$nm_connect = new mysqli($host, $nm_user, $nm_pword, $nm_name);
if (!$nm_connect)
throw new Exception('Could not connect to NM database currently');
else
return $nm_connect;
}
And, in the second case, you'd first define the constants :
define('DB_HOST', 'localhost');
define('DB_DBNAME', 'myname_databasename');
define('DB_USER', 'myname_dbusername');
define('DB_PASSWORD', 'password');
And, then, use those constants :
// db connect to nm database
function db_connect_nm()
{
$nm_connect = new mysqli(DB_HOST, DB_USER, DB_PASSWORD, DB_DBNAME);
if (!$nm_connect)
throw new Exception('Could not connect to NM database currently');
else
return $nm_connect;
}
This second solution is probably more clean than the first one ;-)
Your connection variables are not scoped inside the connection function. You either need to pass them as parameters to the function (preferable) or use the global keyword inside to reference them:
function db_connect_nm($host, $nm_user, $nm_pword, $nm_name)
{
$nm_connect = new mysqli($host, $nm_user, $nm_pword, $nm_name);
//etc...
}
Alternate, not preferred:
function db_connect_nm()
{
global $host, $nm_user, $nm_pword, $nm_name;
$nm_connect = new mysqli($host, $nm_user, $nm_pword, $nm_name);
//etc...
}

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