PHP MySQL Database Connection

Code for Establishing a database connection with MySQL Database using MySqli Extension

 
      <?php 
    #Establishing a connection with the database
     function OpenCon()
     {
     $dbhost = "localhost";
     $dbuser = "root";
     $dbpass = "1234";
     $db = "satish";
     $conn = new mysqli($dbhost, $dbuser,"",$db) or die("Connect failed: %s\n". $conn -> error);
     return $conn;
     }
     
    function CloseCon($conn)
     {
     $conn -> close();
     }

     $conn = OpenCon();
     echo "Connected Successfully";
     CloseCon($conn);
?>
    
Output

Code for inserting a record into the MySQL Database

 
      <?php 
    #inserting a record in a table
     function OpenCon()
     {
     $dbhost = "localhost";
     $dbuser = "root";
     $dbpass = "1234";
     $db = "satish";
     $conn = new mysqli($dbhost, $dbuser,"",$db) or die("Connect failed: %s\n". $conn -> error);
     return $conn;
     }
     
    function CloseCon($conn)
     {
     $conn -> close();
     }

     $conn = OpenCon();
     echo "Connected Successfully";
     $sql = "INSERT INTO employee (eid,name,phone,salary) VALUES ('12456', 'Mathew', 55555,10090)";

      if ($conn->query($sql) === TRUE) {
        echo "New record created successfully";
      } else {
        echo "Error: " . $sql . "<br>" . $conn->error;
      }

      CloseCon($conn);
?>
    
Output

Code for updating a record in the MySQL Database

 
      <?php 
    #updating a record using the primary key in the database
     function OpenCon()
     {
     $dbhost = "localhost";
     $dbuser = "root";
     $dbpass = "1234";
     $db = "satish";
     $conn = new mysqli($dbhost, $dbuser,"",$db) or die("Connect failed: %s\n". $conn -> error);
     return $conn;
     }
     
    function CloseCon($conn)
     {
     $conn -> close();
     }

     $conn = OpenCon();
     echo "Connected Successfully";
     
      $sql = "UPDATE employee SET name='Chris' WHERE eid=12456";

      if ($conn->query($sql) === TRUE) {
        echo "Record updated successfully";
      } else {
        echo "Error updating record: " . $conn->error;
      }
     CloseCon($conn);
?>
    
Output

Code for selecting records from a MySQL Database

 
      <?php 
    #Selecting all the records from a table
     function OpenCon()
     {
     $dbhost = "localhost";
     $dbuser = "root";
     $dbpass = "1234";
     $db = "satish";
     $conn = new mysqli($dbhost, $dbuser,"",$db) or die("Connect failed: %s\n". $conn -> error);
     return $conn;
     }
     
    function CloseCon($conn)
     {
     $conn -> close();
     }

     $conn = OpenCon();
     $sql = "SELECT eid,name FROM employee";
     $result = $conn->query($sql);

   if ($result->num_rows > 0) 
   {
  // output data of each row
    while($row = $result->fetch_assoc()) 
    {
    echo "eid: " . $row["eid"]. " - Name: " . $row["name"]."<br>";
    }
   } else 
   {
    echo "0 results";
   }
  
  CloseCon($conn);
?>
    
Output

Code for searching a record from the database

 
      <?php 
    #Selecting all the records from a table
     function OpenCon()
     {
     $dbhost = "localhost";
     $dbuser = "root";
     $dbpass = "1234";
     $db = "satish";
     $conn = new mysqli($dbhost, $dbuser,"",$db) or die("Connect failed: %s\n". $conn -> error);
     return $conn;
     }
     
    function CloseCon($conn)
     {
     $conn -> close();
     }

     $conn = OpenCon();
     $sql = "SELECT eid,name FROM employee where eid=12456";
     $result = $conn->query($sql);

   if ($result->num_rows > 0) 
   {
  // output data of each row
    while($row = $result->fetch_assoc()) 
    {
    echo "eid: " . $row["eid"]. " - Name: " . $row["name"]."<br>";
    }
   } else 
   {
    echo "0 results";
   }
  
  CloseCon($conn);
?>
    
Output

Code for Deleting a record from the MySQL Database

 
      <?php 
    #Deleting a record from the mysql table
     function OpenCon()
     {
     $dbhost = "localhost";
     $dbuser = "root";
     $dbpass = "1234";
     $db = "satish";
     $conn = new mysqli($dbhost, $dbuser,"",$db) or die("Connect failed: %s\n". $conn -> error);
     return $conn;
     }
     
    function CloseCon($conn)
     {
     $conn -> close();
     }

     $conn = OpenCon();
     $sql = "delete from employee where eid=12457";
     if ($conn->query($sql) === TRUE) {
      echo "Record deleted successfully";
    } else {
      echo "Error deleting record: " . $conn->error;
    }
  CloseCon($conn);
?>

    
Output

Code Demonstrating parameters of MySQLi class

 
      <?php 
     #parameters of mysqli class
     function OpenCon()
     {
     $dbhost = "localhost";
     $dbuser = "root";
     $dbpass = "1234";
     $db = "satish";
     $conn = new mysqli($dbhost, $dbuser,"",$db) or die("Connect failed: %s\n". $conn -> error);
     return $conn;
     }
    function CloseCon($conn)
     {
     $conn -> close();
     }
     $conn = OpenCon();
     echo "Connected Successfully";
     echo $conn->host_info; echo "<br>";
     echo $conn->protocol_version;echo "<br>"; 
     echo $conn->server_info;echo "<br>";
     echo $conn->server_version;echo "<br>";
     echo $conn->client_info;echo "<br>"; 
     echo $conn->client_version;echo "<br>"; 
     CloseCon($conn);
?>
    
Output

PHP Data Objects
Establishing a Database connection using Php Data objects

 
      <?php 
    #PHP Data Objects
    $dbHost="localhost";  
    $dbName="satish";  
    $dbUser="root";      //by default root is user name.  
    $dbPassword="";     //password is blank by default  
    try{  
        $dbConn= new PDO("mysql:host=$dbHost;dbname=$dbName",$dbUser,$dbPassword);  
        Echo "Successfully connected with database Satish";  
    } catch(Exception $e){  
    Echo "Connection failed" . $e->getMessage();  
    }  
    // this command close the connection.  
    $dbConn = null;   
?>
    
Output

Inserting a Record using Php Data objects

 
      <?php 
    #PHP Data Objects
    $dbHost="localhost";  
    $dbName="satish";  
    $dbUser="root";      //by default root is user name.  
    $dbPassword="";     //password is blank by default  
    try{  
        $dbConn= new PDO("mysql:host=$dbHost;dbname=$dbName",$dbUser,$dbPassword);  
        Echo "Successfully connected with database Satish";  
        $query = $dbConn->exec("insert into employee values('124','ram',2333,566);"); // returns number of affected rows
        if($query)
        {
          echo "Row Inserted";
        }
    } catch(Exception $e){  
    Echo "Connection failed" . $e->getMessage();  
    }  
    // this command close the connection.  
    $dbConn = null;      
?>

    
Output

Updating a record in the database using PhP Data Objects

 
      <?php 
    #PHP Data Objects
    $dbHost="localhost";  
    $dbName="satish";  
    $dbUser="root";      //by default root is user name.  
    $dbPassword="";     //password is blank by default  
    try{  
        $dbConn= new PDO("mysql:host=$dbHost;dbname=$dbName",$dbUser,$dbPassword);   
        $query = $dbConn->exec("update employee set name='tom' where eid='124';"); // returns number of affected rows
        if($query)
        {
          echo "Row Updated Successfully";
        }
    } catch(Exception $e){  
    Echo "Connection failed" . $e->getMessage();  
    }  
    // this command close the connection.  
    $dbConn = null;      
?>
    
Output

Deleting a record from the table using PHP Data Objects

 
      <?php 
    #PHP Data Objects
    $dbHost="localhost";  
    $dbName="satish";  
    $dbUser="root";      //by default root is user name.  
    $dbPassword="";     //password is blank by default  
    try{  
        $dbConn= new PDO("mysql:host=$dbHost;dbname=$dbName",$dbUser,$dbPassword);   
        $query = $dbConn->exec("delete from employee where eid='124';"); // returns number of affected rows
        if($query)
        {
          echo "Row Deleted Successfully";
        }
    } catch(Exception $e){  
    Echo "Connection failed" . $e->getMessage();  
    }  
    // this command close the connection.  
    $dbConn = null;      
?>
    
Output

Selecting Records from a table using PHP Data Objects

 
      <?php 
    #PHP Data Objects - selecting records from a table
    $dbHost="localhost";  
    $dbName="satish";  
    $dbUser="root";      //by default root is user name.  
    $dbPassword="";     //password is blank by default  
    try{  
        $dbConn= new PDO("mysql:host=$dbHost;dbname=$dbName",$dbUser,$dbPassword);   
        $query = $dbConn->query("select * from employee;"); 
        foreach($query as $row)
        {
           echo $row['eid'];
           echo $row['name'];
           echo $row['phone'];
           echo $row['salary'];
           echo "<br>";
        }
    } catch(Exception $e){  
    Echo "Connection failed" . $e->getMessage();  
    }  
    // this command close the connection.  
    $dbConn = null;      
?>
    
Output

Writing the data from a table as an HTML table to the client using PHP

 
      <!DOCTYPE html>
<html lang="en">
<head>
     <meta charset="UTF-8">
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Document</title>
     <style>
          table th{
               background-color: aqua;}
          tr:nth-child(2n+1)
          {
               background-color:bisque;
          }
     
     </style>
</head>
<body>
     
</body>
</html>
<?php 
    #Selecting all the records from a table
     function OpenCon()
     {
     $dbhost = "localhost";
     $dbuser = "root";
     $dbpass = "1234";
     $db = "satish";
     $conn = new mysqli($dbhost, $dbuser,"",$db) or die("Connect failed: %s\n". $conn -> error);
     return $conn;
     }
     
    function CloseCon($conn)
     {
     $conn -> close();
     }

     $conn = OpenCon();
     $sql = "SELECT * FROM employee";
     $result = $conn->query($sql);

   if ($result->num_rows > 0) 
   {
     echo "<table border='1'>
     <tr>
     <th>Employee Id</th>
     <th>Name</th>
     <th>Phone</th>
     <th>Salary</th>
     </tr>";
  // output data of each row
    while($row = $result->fetch_assoc()) 
    {
          echo "<tr>";
          echo "<td>" . $row['eid'] . "</td>";
          echo "<td>" . $row['name'] . "</td>";
          echo "<td>" . $row['phone'] . "</td>";
          echo "<td>" . $row['salary'] . "</td>";
          echo "</tr>";
    }
    echo "</table>";
   } else 
   {
    echo "0 results";
   }
  
  CloseCon($conn);
?>
    
Output