Wednesday, 6 July 2016

Get Radius in Miles using Latitude & Longitude in MySQL

Here is the trick to find the radius distance in miles directly from the latitude & longitude data store in your mysql table. This is a very helpful trick which i use while creating webservices for mobile apps.

  id, (
    3959 * acos (
      cos ( radians(78.3232) )
      * cos( radians( lat ) )
      * cos( radians( lng ) - radians(65.3234) )
      + sin ( radians(78.3232) )
      * sin( radians( lat ) )
  ) AS distance
FROM markers
HAVING distance < 30
ORDER BY distance
LIMIT 0 , 20;

Monday, 1 February 2016

Circuit Scribe

A new innovative technique to create electronics circuit with very low cost materials on the paper, checkout the video.

Sunday, 3 January 2016

Know Your Provident Fund Balance.

Ever wondered that how much money has been submitted by your employer, you can checkout your EPF (Employer' Provident Balance) just by the click of the mouse.
Here is the link for checking the link for it.


Just fill the form and you will get the provident fund balance to the phone number mentioned by your employer.

Monday, 9 November 2015

Must Know PhoneGap CLIs

In order to deal with phonegap, you should be very handy with the initial command line interface of phonegap, this is one of the cool feature of  which lets you work very quickly and create apps with an ease, so I am going to write the  list of some must know commands which are very helpful while developing a phonegap app

Install Phonegap/Cordova

npm install -g cordova

Create an App

cordova create my-app

Create Platforms, which lets you run your code in different OS

cordova platform add ios
cordova platform add amazon-fireos
cordova platform add android
cordova platform add blackberry10
cordova platform add firefoxos

Remove Platforms

cordova platform rm android

Build App

cordova build
cordova build ios

Test App on Emulator

cordova emulate android

Add a plugin to your app

cordova plugin add
cordova plugin add
cordova plugin add

Remove a plugin

cordova plugin rm

List all the plugins added in the mobile app

cordova plugins ls


cordova help
cordova info

Update Platform

cordova platform update android
cordova platform update ios

Run Phonegap/Cordova app

cordova run android
cordova run ios


Get Started With PHONEGAP

This is an very interested blog about creating a mobile app with one of the latest and noted technology called PHONEGAP. I was wondering that when i will get a chance to create a mobile application, Everytime probably i was stuck between the discussion of native VS hybrid everytime. As a Web programmer my strength was always server side programming language which is PHP & client side languages like HTML, CSS, JavaScript & jQuery.

Every time i felt that learning android development using java is better than creating mobile app using phonegap's javascript's framework,because i felt the framework of phonegap would be little difficult to learn, then why not try out the android's java framework if you are giving the same effort for learning, also it has many supporting blogs now a days. One day i got a project from one of a client who was looking for an app to be developed using Phonegap and i was very excited to start it, and trust me it took me a little while to learn the initial things of framework, its damn easy and you can create big web based apps with an ease and with the same team which are creating web version.

So Here are the pre-requisite things which is required if you want to kick start with phonegap.
1).A Good Experience in HTML 5 tags.
2).Good Exposure towards CSS 3.
3).A Good Knowledge in Javascript Or jQuery, if you know any good javascript framework like angular or NodeJS then it will be awesome for you.
4).And a little experience about the mobile environment, mobile development life cycles etc.

Now to get Started just follow few steps and you will be ready to start.

1).Install Git.
2).Install Node Js command line tool, visit official site of nodeJs and download their tool.
3).Download & Install JDK.
4).Download Android SDK tools.
5).Download & Install Apache ANT(Download the zip File and extract it somewhere).

Now the next step is new environment variables.

1). Create the environment variable for latest jdk bin folder, in my case it was C:\Program Files\Java\jdk1.8.0_65\bin
2). Create the environment variable for latest Apache ANT bin folder, in my case I have just extracted the zip file in C: Drive and gave the path like this C:\apache-ant-1.9.6\bin
3). Now give the path of the Android SDK folder.
4). Now give the path of build-tools(folder) in the environmental variable.
5). Now give the path of tools (folder) in the environmental variable.
6). Now give the path of platform-tools (folder) in the environmental variable.
7). Now give the path of platforms (folder)

Add all the path one by one separated a semicolon

That's it now you are ready to go.

Now to make sure, everything is set, open your NODE JS command prompt and write a command "java", if it gives any info reagarding java then, the environmental variable has been set correctly.

Now we will install phonegap into our computer, to do that just write the command
npm install -g phonegap


npm install -g cordova

Cordova is the latest version phonegap engine, which is a collaborated open source version of phonegap & Apache, installing the cordova or phonegap would take few minutes or may be little more which depends on your internet connection, if you have installed cordova then always the word cordova in the command lines instead of phonegap.

after this we can create our first project in phone gap as shown below.

phonegap create MyFirstPhoneGapProject

This command will create your first phonegap project in your computer.
Now to run your first phonegap project, you have to add a platform in your phonegap project folder, if you are using android phonegap then add android platform or else IOS or whatever. To add a platform in your phonegap project  you have to write the command like this.

phonegap platform add android

this command will add all pre-requisite dependency files for android app development, so that it would  be ready to go for your android phone once you launch it.

Now finally we have to run the project in a real device, so now just connect your android phone to computer, also make sure the developer options like USB debugging of your android phone is enabled. Now run a test command.

adb devices

This will show the list of mobile devices connected to the computer, if the list is empty then disconnect and connect the phone again.

Now Run your first app by running this code.

cordova run android
phonegap run android

and this will install your phonegap app into your phone.

If you have not connected any phone to your computer then phonegap will run the app in the android default emulator.

Thursday, 24 September 2015

Stored Procedures in MySQL

Stored Procedures in MySQL

The MySQL database supports stored procedures. A stored procedure is a subroutine stored in the database catalog. Applications can call and execute the stored procedure. The CALL SQL statement is used to execute a stored procedure.
Stored procedures can have IN, OUT & INOUT parameters, depending on the MySQL version. The mysqli interface has no special notion for the different kinds of parameters.

Usually stored procedures are not used in the PHP Development, but still its a useful option for reducing the query writing practice.

Some examples of stored procedures with different types are as follow.

IN parameter

To create a stored procedure with in parameter you can write a query like this.

INSERT INTO test(id) VALUES(id_val);

Now to call the stored procedures you can do something like this.

CALL p(1);

OUT parameter

To create a store procedure with inout/out parameter you can write a query like as following.

 IN orderStatus VARCHAR(25),
 OUT total INT)
 SELECT count(orderNumber)
 INTO total
 FROM orders
 WHERE status = orderStatus;

Now to call the stored procedures you can do something like this.

CALL CountOrderByStatus('Shipped',@total);

if you want to execute a php code, you can write like this

$result=mysql_query("CALL CountOrderByStatus('Shipped',@total)");

INOUT parameter

To create a store procedure with inout/out parameter you can write a query like as following,
INOUT exactly works like the OUT parameter

CREATE PROCEDURE set_counter(INOUT count INT(4),IN inc INT(4))
 SET count = count + inc;

Now to call the stored procedures you can do something like this.

CALL set_counter(@counter,1);

That's it, its damn easy to go on with.