Tuesday 28 April 2015

Difference between On Delete Cascade & On Update Cascade in mysql

My Parent Table
CREATE TABLE parent (
    id INT NOT NULL,
    PRIMARY KEY (id)
) ENGINE=INNODB;
1)

CREATE TABLE child (
    id INT, 
    parent_id INT,
    INDEX par_ind (parent_id),
    FOREIGN KEY (parent_id) 
        REFERENCES parent(id)
        ON DELETE CASCADE
) ENGINE=INNODB;

2)

CREATE TABLE child (
    id INT, 
    parent_id INT,
    INDEX par_ind (parent_id),
    FOREIGN KEY (parent_id) 
        REFERENCES parent(id)
        ON UPDATE CASCADE
) ENGINE=INNODB;

3)

CREATE TABLE child (
        id INT, 
        parent_id INT,
        INDEX par_ind (parent_id),
        FOREIGN KEY (parent_id) 
            REFERENCES parent(id)
            ON UPDATE CASCADE ON DELETE CASCADE
    ) ENGINE=INNODB;

What do these queries (1,2 & 3) mean?? Are they same???

1) means that if the parent is deleted, the child is also deleted 

2) means that if the parent primary key is changed, the child value will also change to reflect that - again in my opinion, not a great idea. If you're changing PRIMARY KEYs with any regularity (or even at all), there's something wrong with your design.

3) Means that if you update or delete the parent, the change is cascaded to the child.

Saturday 18 April 2015

what is the use of time_sleep_until() function in php ?

The time_sleep_until() function delays execution of the current script until the specified time.

Syntax
time_sleep_until(timestamp)

Example 

Delay the execution of the current script until 10 seconds:

<?php
// wake up ten seconds from now
time_sleep_until(time()+10);
?>

What is the use of sleep() function ?

The sleep() function delays execution of the current script for a specified number of seconds.

Example 
<?php
echo date('h:i:s') . "<br>";

//sleep for 5 seconds
sleep(5);

//start again
echo date('h:i:s');
?>

Friday 17 April 2015

Inviting facebook friends to your website using javascript SDK

Hi guys,

Today I am going to share some interesting news.  Now a days everyone having a website but they dont know how to market it. I am going to share how to send a invitation about your website to your facebook friends.


Here we follow only 5 Steps

Step 1 : you have to create a application in facebook  – https://developers.facebook.com/apps 
Step 2: After creating facebook application – get your facebook app id 
Step 3 : Insert this  sdk before head tag

<script src="http://connect.facebook.net/en_US/all.js"></script>

Step 4 :

Insert this javascript code in your web page

FB.init({
 appId:'your app id', cookie:true, status:true, xfbml:true
 });
function FacebookInviteFriends()
{
FB.ui({ method: 'send',name: 'Complete Web Tutorials - PHP, Mysql, Ajax, Jquery, HTML, CSS, facebook, twitter',link: 'http://w3lessons.info', description: 'your website description', picture: 'http://w3lessons.info/demo/web2.0.jpg'});
}

Step 5: call the facebookinvitefriends function via this link

<a href="#" onclick="FacebookInviteFriends();">Bring Your Friends</a>

thats it man.. you are done!! Finally Message will appear in your friends inbox like this



Referece Website : 
http://w3lessons.info/2012/10/15/inviting-facebook-friends-to-your-website-using-javascript-sdk/

Place Autocomplete Address Form using google api

Place Autocomplete Address Form
Street address
City
State Zip code
Country

Source

<!DOCTYPE html>
<html>
  <head>
    <title>Place Autocomplete Address Form</title>
    <meta name="viewport" content="initial-scale=1.0, user-scalable=no">
    <meta charset="utf-8">
    <style>
      html, body, #map-canvas {
        height: 100%;
        margin: 0px;
        padding: 0px
      }
    </style>
    <link type="text/css" rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:300,400,500">
    <script src="https://maps.googleapis.com/maps/api/js?v=3.exp&signed_in=true&libraries=places"></script>
    <script>
// This example displays an address form, using the autocomplete feature
// of the Google Places API to help users fill in the information.

var placeSearch, autocomplete;
var componentForm = {
  street_number: 'short_name',
  route: 'long_name',
  locality: 'long_name',
  administrative_area_level_1: 'short_name',
  country: 'long_name',
  postal_code: 'short_name'
};

function initialize() {
  // Create the autocomplete object, restricting the search
  // to geographical location types.
  autocomplete = new google.maps.places.Autocomplete(
      /** @type {HTMLInputElement} */(document.getElementById('autocomplete')),
      { types: ['geocode'] });
  // When the user selects an address from the dropdown,
  // populate the address fields in the form.
  google.maps.event.addListener(autocomplete, 'place_changed', function() {
    fillInAddress();
  });
}

// [START region_fillform]
function fillInAddress() {
  // Get the place details from the autocomplete object.
  var place = autocomplete.getPlace();

  for (var component in componentForm) {
    document.getElementById(component).value = '';
    document.getElementById(component).disabled = false;
  }

  // Get each component of the address from the place details
  // and fill the corresponding field on the form.
  for (var i = 0; i < place.address_components.length; i++) {
    var addressType = place.address_components[i].types[0];
    if (componentForm[addressType]) {
      var val = place.address_components[i][componentForm[addressType]];
      document.getElementById(addressType).value = val;
    }
  }
}
// [END region_fillform]

// [START region_geolocation]
// Bias the autocomplete object to the user's geographical location,
// as supplied by the browser's 'navigator.geolocation' object.
function geolocate() {
  if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(function(position) {
      var geolocation = new google.maps.LatLng(
          position.coords.latitude, position.coords.longitude);
      var circle = new google.maps.Circle({
        center: geolocation,
        radius: position.coords.accuracy
      });
      autocomplete.setBounds(circle.getBounds());
    });
  }
}
// [END region_geolocation]

    </script>

    <style>
      #locationField, #controls {
        position: relative;
        width: 480px;
      }
      #autocomplete {
        position: absolute;
        top: 0px;
        left: 0px;
        width: 99%;
      }
      .label {
        text-align: right;
        font-weight: bold;
        width: 100px;
        color: #303030;
      }
      #address {
        border: 1px solid #000090;
        background-color: #f0f0ff;
        width: 480px;
        padding-right: 2px;
      }
      #address td {
        font-size: 10pt;
      }
      .field {
        width: 99%;
      }
      .slimField {
        width: 80px;
      }
      .wideField {
        width: 200px;
      }
      #locationField {
        height: 20px;
        margin-bottom: 2px;
      }
    </style>
  </head>

  <body onload="initialize()">
    <div id="locationField">
      <input id="autocomplete" placeholder="Enter your address"
             onFocus="geolocate()" type="text"></input>
    </div>

    <table id="address">
      <tr>
        <td class="label">Street address</td>
        <td class="slimField"><input class="field" id="street_number"
              disabled="true"></input></td>
        <td class="wideField" colspan="2"><input class="field" id="route"
              disabled="true"></input></td>
      </tr>
      <tr>
        <td class="label">City</td>
        <td class="wideField" colspan="3"><input class="field" id="locality"
              disabled="true"></input></td>
      </tr>
      <tr>
        <td class="label">State</td>
        <td class="slimField"><input class="field"
              id="administrative_area_level_1" disabled="true"></input></td>
        <td class="label">Zip code</td>
        <td class="wideField"><input class="field" id="postal_code"
              disabled="true"></input></td>
      </tr>
      <tr>
        <td class="label">Country</td>
        <td class="wideField" colspan="3"><input class="field"
              id="country" disabled="true"></input></td>
      </tr>
    </table>
  </body>

</html>

Reference URL:
http://ubilabs.github.io/geocomplete/


Wednesday 1 April 2015

What is the use of preventDefault() ?



The event.preventDefault() method stops the default action of an element from happening.

Difference b/w attr() and prop() /



An input field can have the attribute "value". This will equal the default value you entered. If the user changes the value in the input field, the property "value" changes in the DOM Tree, but the original attribute is left remaining.

So basically, if you want the default value setup for an HTML tag's attribute, use the .attr() function. If you that value can be changed by the user (such as inputs, checkbox's, radios, etc.) use the .prop() function to get the newest value.

What is the use of serialize() ?

The serialize() method creates a URL encoded text string by serializing form values.
You can select one or more form elements (like input and/or text area), or the form element itself.
The serialized values can be used in the URL query string when making an AJAX request.

<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
<script>
$(document).ready(function(){
    $("button").click(function(){
        $("div").text($("form").serialize());
    });
});
</script>
</head>
<body>

<form action="">
  First name: <input type="text" name="FirstName" value="Mickey"><br>
  Last name: <input type="text" name="LastName" value="Mouse"><br>
</form>

<button>Serialize form values</button>

<div></div>

</body>
</html>

How to find given date is Sunday or not ?

<?php
function findleave($systemtardt)
{
    $comity_dt=date('Y-m-d',strtotime($systemtardt));

    $inputDateArray = explode('-', $comity_dt);
    if(date('N', mktime (0, 0 , 0, $inputDateArray[1], $inputDateArray[2], $inputDateArray[0])) == 7)
    {
        return "1";  //sunday
    }
    else
    {
        return "0";
    }
                   
}

if(isset($_REQUEST['findleave']))
{
    echo findleave($_REQUEST['dp']);
}
?>
<form name="test" method="post">
<input type="text" name="dp" />
<input type="submit" name="findleave" />
</form>

How to check atleast any one radio button checked using javascript ?

var chkbox_val=document.getElementsByName('mat_reqdetid[]');
       
        var flag=1;
        for(var c=0;c<chkbox_val.length;c++)
        {
            if(chkbox_val[c].value=='')
            {
                flag=0;
            }
        }
       
        if(flag==0)
        {
            jAlert("Select Any One Product");
        }

Difference b/w assign() and replace() ?



Using window.location.assign("url") will just cause a new document to load. Using window.location.replace("url") will replace the current document and replace the current History with that URL making it so you can't go back to the previous document loaded.

Count duplicate record’s using mysql ?



SELECT name, COUNT(*) AS times, IF (COUNT(*)>1,"duplicated", "not duplicated") AS duplicated FROM <MY_TABLE> GROUP BY name

ANS: AAA 2 duplicated
     BBB 3 duplicated
     CCC 1 not duplicated