//Mysql_connect() example without using hostname:port syntax

<?php
$link = mysql_connect(`localhost`, `mysql_user`, `mysql_password`);
if (!$link) {
die(`Could not connect: ` . mysql_error());
}
echo `Connected successfully`;
mysql_close($link);
?>

//Mysql_connect() example using hostname:port syntax

<?php
$link = mysql_connect(`localhost:mysqlport`, `mysql_user`, `mysql_password`);
if (!$link) {
die(`Could not connect: ` . mysql_error());
}
echo `Connected successfully`;
mysql_close($link);
?>

// Main Connection Class ........................
<?php
class WADB
{
/* Database Host */
public $sDbHost;
public $sDbName; // Database Name
public $sDbUser; // Database User
public $sDbPwd; // Database Password
public $sDbDetail; // Database Details
public $iNoOfRecords; // Total No of Records
public $oQueryResult; // Results of sql query
public $aSelectRecords; // Array
public $bSelectRecords; // Array
public $aArrRec; // Array
public $bInsertRecords; // Boolean
public $iInsertRecId; // Integer - the primary key for inserted record
public $bUpdateRecords; // Boolean

/* Constructor */
function WADB ($sDbHost, $sDbName, $sDbUser, $sDbPwd)
{
$oDbLink = mysql_connect ($sDbHost, $sDbUser, $sDbPwd) or die ("MySQL DB could not be connected");
mysql_select_db ($sDbName, $oDbLink)or die ("MySQL DB could not be selected");
}

/* Select Records */
function selectRecords($sSqlQuery)
{
//if(isset($this->aSelectRecords)){
unset($this->bSelectRecords);
$this->oQueryResult = mysql_query($sSqlQuery) or die(mysql_error());
$this->iNoOfRecords = mysql_num_rows($this->oQueryResult);
if ($this->iNoOfRecords > 0) {
while ($oRow = mysql_fetch_array($this->oQueryResult)) {
$this->bSelectRecords[] = $oRow;
}
mysql_free_result($this->oQueryResult);
}
$this->aArrRec = $this->bSelectRecords;
//}
return $this->aArrRec;
}

/*Get Number of Records */
function getNumberOfRecords () {
return $this->iNoOfRecords;
}

/* Get selected data */
function getSelectedData (){
return $this->aSelectRecords;
}

/* Insert Records */
function insertRecords($sSqlQuery)
{
$this->bInsertRecords = mysql_query ($sSqlQuery) or die (mysql_error());
$this->iInsertRecId = mysql_insert_id();
return $this->iInsertRecId;
}

/* Find Inserted Id */
function getIdForInsertedRecord()
{
return $this->iInsertRecId;
}

/* Update Records */
function updateRecords($sSqlQuery)
{
return mysql_query($sSqlQuery) or die(mysql_error());
}
function deleteRecords($sSqlQuery)
{
return mysql_query($sSqlQuery) or die(mysql_error());
}
}
?>

// Implementing WADB Class..............................................
<?php
class SiteData
{
var $oDb; // Database Object
var $sSql; // Contains sql statements

/* Costructor, connecting to the database & returning a connection object */
function SiteData()
{
$this->oDb = new WADB(SYSTEM_DBHOST, SYSTEM_DBNAME, SYSTEM_DBUSER, SYSTEM_DBPWD);
return TRUE;
}
function getData($sSql)
{
$hData = $this->oDb->selectRecords($sSql);
$iNumOfItems = $this->oDb->getNumberOfRecords();
$ahomeData = array(`NO_OF_ITEMS`=>$iNumOfItems, `oDATA`=>$hData);
return $ahomeData ;
}

function inserttoDB($sSql)
{
$iData = $this->oDb->insertRecords($sSql);
$insertArray=array(`oDATA`=>$iData);
return $insertArray;
}
function update($sSql)
{
$hData = $this->oDb->updateRecords($sSql);
}
function deleterecord($sSql)
{
$iData = $this->oDb->deleteRecords($sSql);
$insertArray=array(`oDATA`=>$iData);
return $insertArray;
}

}
?>

// Now define the database information as:

<?php
define(`SYSTEM_DBHOST`,`localhost`);
define (`SYSTEM_DBNAME`,`janaki`);
define (`SYSTEM_DBUSER`,`root`);
define (`SYSTEM_DBPWD`,`root`);
?>

Click here to download this file

<?php
$dbconn = pg_connect("dbname=mary");
//connect to a database named "mary"

$dbconn2 = pg_connect("host=localhost port=5432 dbname=mary");
// connect to a database named "mary" on "localhost" at port "5432"

$dbconn3 = pg_connect("host=sheep port=5432 dbname=mary user=lamb password=foo");
//connect to a database named "mary" on the host "sheep" with a username and password

$conn_string = "host=sheep port=5432 dbname=test user=lamb password=bar";
$dbconn4 = pg_connect($conn_string);
//connect to a database named "test" on the host "sheep" with a username and password
?>


The connection_string can be empty to use all default parameters, or it can contain one or more parameter settings separated by whitespace. Each parameter setting is in the form keyword = value. Spaces around the equal sign are optional. To write an empty value or a value containing spaces, surround it with single quotes, e.g., keyword = `a value`. Single quotes and backslashes within the value must be escaped with a backslash, i.e., ` and .

The currently recognized parameter keywords are: host, hostaddr, port, dbname, user, password, connect_timeout, options, tty (ignored), sslmode, requiressl (deprecated in favor of sslmode), and service. Which of these arguments exist depends on your PostgreSQL version.

Syntax
odbc_connect ( string $dsn , string $user , string $password [, int $cursor_type ] )

DNS-less connections:
<?php
// Microsoft SQL Server using the SQL Native Client 10.0 ODBC Driver - allows connection to SQL 7, 2000, 2005 and 2008
$connection = odbc_connect("Driver={SQL Server Native Client 10.0};Server=$server;Database=$database;", $user, $password);

// Microsoft Access
$connection = odbc_connect("Driver={Microsoft Access Driver (*.mdb)};Dbq=$mdbFilename", $user, $password);

// Microsoft Excel
$excelFile = realpath(`C:/ExcelData.xls`);
$excelDir = dirname($excelFile);
$connection = odbc_connect("Driver={Microsoft Excel Driver (*.xls)};DriverId=790;Dbq=$excelFile;DefaultDir=$excelDir" , ``, ``);
?>

<?php
define('SYSTEM_DBUSER','USERNAME');
define('SYSTEM_DBPWD','PASSWORD');
define('SYSTEM_DBNAME','DB_OR_SCHEMA');
$db_conn=oci_connect(SYSTEM_DBUSER,SYSTEM_DBPWD,SYSTEM_DBNAME) or die ("DB could not be connected");

?>