Tag: php

UPDATE / EDIT Records In Database Table: PHP & MySQL

Video tutorial demonstrates updating / editing of data / records from the database table and displaying it on the browser.

First look at these short videos:
Connect to the database
Simple / basic insertion operation
Insertion of Records into Database using Forms: PHP & MySQL (important)
SELECT / LIST Records From Database Table: PHP & MySQL

Source Code: SELECTING and Displaying Data

index.php

<?php

include_once('db.php');
 
if(isset($_POST['name']))
{
  $name = $_POST['name'];
 
  if(mysql_query("INSERT INTO apple VALUES('','$name')"))
echo "Successful Insertion!";
  else
echo "Please try again";
}
 
 
$res = mysql_query("SELECT * FROM apple");
 
 
?>
 
<form action="." method="POST">
Name: <input type="text" name="name"/><br />
<input type="submit" value=" Enter "/>
</form>
 
<h1>List of companies ..</h1>
< ?php
while( $row = mysql_fetch_array($res) )
  echo "$row[id]. $row[name] 
                <a href='edit.php?edit=$row[id]'>edit<br />";
?>

Video Tutorial: UPDATE / EDIT Records In Database Table: PHP & MySQL


[youtube https://www.youtube.com/watch?v=Hw1MwUlekeo]

https://www.youtube.com/watch?v=Hw1MwUlekeo [Watch the Video In Full Screen.]


Source Code: Updating / Editing Data / Records In The Database Table

edit.php

<?php
include_once('db.php');
 
if( isset($_GET['edit']) )
{
$id = $_GET['edit'];
$res= mysql_query("SELECT * FROM apple WHERE id='$id'");
$row= mysql_fetch_array($res);
}
 
if( isset($_POST['newName']) )
{
$newName = $_POST['newName'];
$id   = $_POST['id'];
$sql     = "UPDATE apple SET name='$newName' WHERE id='$id'";
$res  = mysql_query($sql) 
                                    or die("Could not update".mysql_error());
echo "<meta http-equiv='refresh' content='0;url=index.php'>";
}
 
?>

<form action="edit.php" method="POST">
Name: <input type="text" name="newName" value="<?php echo $row[1]; ?/>"><br />
<input type="hidden" name="id" value="<?php echo $row[0]; ?/>">
<input type="submit" value=" Update "/>
</form>

meta tag used to redirect to other page..

<meta http-equiv='refresh' content='0;url=index.php'>

MySQL Query

mysql> UPDATE apple SET name='newName' WHERE id='session_id';

Security Issue:
Make sure not to allow people to explicitly pass random id’s and retrieve and edit/update other’s data. To solve this issue, you can save the id of the logged in user in a session variable and instead of passing id to edit.php we can directly use the id stored in our session variable.
This would solve the issue.

Output: After Updating the records:

  1. Google USA
  2. Apple USA
  3. Microsoft USA
  4. Oracle USA
  5. Technotip IN

Video’s To Watch:
GET method in action
Post method in action
session variable basics
User login and session

SELECT / LIST Records From Database Table: PHP & MySQL

Video tutorial demonstrates selecting / listing / fetching of data / records from the database table and displaying it on the browser.

First look at these short videos:
Connect to the database
Simple / basic insertion operation
Insertion of Records into Database using Forms: PHP & MySQL (important)

SELECTING and Displaying Data
index.php

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< ?php
  include_once('db.php');
 
 $res = mysql_query("SELECT * FROM apple");
 
  while( $row = mysql_fetch_array($res) )
  echo "$row[id]. $row[name] <br />";
 
?>

Video Tutorial: SELECT / LIST Records From Database Table: PHP & MySQL


[youtube https://www.youtube.com/watch?v=OAT0iTXlqCk]

YouTube Link: https://www.youtube.com/watch?v=OAT0iTXlqCk [Watch the Video In Full Screen.]



Full code
index.php

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< ?php
include_once('db.php');
 
if(isset($_POST['name']))
{
  $name = $_POST['name'];
 
  if(mysql_query("INSERT INTO apple VALUES('','$name')"))
echo "Successful Insertion!";
  else
echo "Please try again";
}
 
 
$res = mysql_query("SELECT * FROM apple");
 
 
?>
 
<form action="." method="POST">
Name: <input type="text" name="name"/><br />
<input type="submit" value=" Enter "/>
</form>
 
<h1>List of companies ..</h1>
< ?php
while( $row = mysql_fetch_array($res) )
  echo "$row[id]. $row[name] <br />";
?>

while loop executes until there is data inside the table, once there is no more data to fetch, loop terminates.

MySQL Query

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mysql> SELECT * FROM apple;

This mysql statement fetches data from all the fields of the table.
We could specify fields and get only list of those values.

Ex:

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mysql> SELECT id FROM apple;

Using this we can get list of id’s only.

After fetching data from table apple

List of companies ..

1. Google
2. Apple
3. Microsoft
4. Oracle
5. Technotip

Insertion of Records into Database: PHP & MySQL

Video tutorial illustrates INSERTION of records into database via PHP script.

Simple / basic insertion operation:

First connect to the database.

Next, using simple MySQL query.
index.php

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< ?php
include_once('db.php');
 
 
if(mysql_query("INSERT INTO apple VALUES('','Oracle')"))
echo "Successful Insertion!";
else
echo "Please try again";
?>

make sure to watch other video about connecting to the database, to understand include_once(‘db.php’);

Video Tutorial: Insertion of Records into Database: PHP & MySQL


[youtube https://www.youtube.com/watch?v=GSLn77qbS1w]

YouTube Link: https://www.youtube.com/watch?v=GSLn77qbS1w [Watch the Video In Full Screen.]



die function:

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< ?php
 
   include_once('db.php');
 
   $res = mysql_query("INSERT INTO apple VALUES('','Oracle')") 
                            or die("sorry, database is busy!");
 
   echo "Successful insertion";
?>

if the insertion operation fails for some reason, the die function is invoked and the message “Sorry, database is busy!” is shown to the use and the script execution halts, and the “Successful insertion” message won’t be echoed.

Data in the database, as shown in the video:
1. Google
2. Apple
3. Microsoft
4. Oracle

Connecting To MySQL server From PHP

Most application programs need to be connected to the database inorder to do some basic operations like saving and retrieving the user details / data.

In this video tutorial we illustrate, how we need to connect to MySQL server from PHP script.

Connecting to MySQL server
db.php

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< ?php
$conn = mysql_connect('localhost','root','');
$db   = mysql_select_db('database_name', $conn);
?>

Include this file in all other files which needs to communicate with this database database_name

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< ?php
include_once('db.php');
?>
 
INSERT, SELECT, UPDATE, DELETE, DROP etc ..operations 
on the datbase.

Video Tutorial: Connecting To MySQL server From PHP


[youtube https://www.youtube.com/watch?v=EAJ0XsQysf8]

YouTube Link: https://www.youtube.com/watch?v=EAJ0XsQysf8 [Watch the Video In Full Screen.]



There are many variations of include:
include();
include_once();

require();
require_once();

require produces fatal error if the required file is not found. include produces warning when the file is not found.
include_once and require_once makes sure the files are included only once and not included multiple times in the same file.

Format Date and Insert Into Database Table: PHP

Convert string type variable data to formatted date type variable and insert it into database table..

Connecting the PHP Script to database
db.php

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< ?php
$conn = mysql_connect("localhost","username","password");
$db      = mysql_select_db("table_name",$conn);
?>

Our database name is technotip and table name is temp.
date-time.php

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< ?php
       include_once('db.php');
 
// [created_at] => Sun Mar 23 06:39:16 +0000 2008
 
$raw = "Sun Mar 23 06:39:16 +0000 2008";
 
$xplod = explode(' ', $raw);
 
print_r($xplod);
 
$string = "$xplod[5]-$xplod[1]-$xplod[2] $xplod[3]";
 
echo "<br />$string";
 
$date = date("Y-m-d H:i:s", strtotime($string));
 
echo "<br />$date";
 
 
if(msql_query("INSERT INTO test VALUES('$date')"))
echo "Inserted successfully!";
else
echo "Failed .. please try again!";
 
?>

Twitter and other API’s return these kind of string Sun Mar 23 06:39:16 +0000 2008
which we store into a variable. using PHP standard function explode we separate the elements based on space.

Video Tutorial: Format Date and Insert Into Database Table: PHP


[youtube https://www.youtube.com/watch?v=SceCb09fwSo]

YouTube Link: https://www.youtube.com/watch?v=SceCb09fwSo [Watch the Video In Full Screen.]



Now we use print_r() function to see the structure of the array:

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Array ( 
  [0] => Sun 
  [1] => Mar 
  [2] => 23 
  [3] => 06:39:16 
  [4] => +0000 
  [5] => 2008 
)

Next, by using its index value we arrange the date according to the format that is suitable to be stored into mysql table.

Convert the string to time format using strtotime() php standard function.

Finally, using date() function match the date formats and store it inside another variable which is then used to pass the date to the database.

Here is the SQL Query:

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INSERT INTO test VALUES('$date')