Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- Equal

  JavaScript: Passing by Value or by Reference

In JavaScript, we have functions and we have arguments that we pass into those functions. But how JavaScript handles what you’re passing in is not always clear. When you start getting into object-oriented development, you may find yourself perplexed over why you have access to values sometimes but not other times. When passing in a primitive type variable like a string or a number, the value is passed in by value. This means that any changes to that variable while in the function are com...

   JavaScript,Function,Pass by reference,Pa     2011-07-28 11:05:25

  <=> operator in MySQL

Have you ever seen "<=>" in a SQL query while using MySQL? Does it mean less and equals to and greater than? Actually if you consider it as the union of <= and =>, great, you are close to it. This is one form of equal operator in MySQL, it has the similar meaning to the = operator with some subtle difference. According to MySQL documentation, <=> is NULL-safe equal. This operator performs an equality comparison like the = operator, but returns 1 rather than NULL if both operand...

   MySQL,NULL safe,<=>     2014-03-24 06:23:22

  Arrays.equals() vs MessageDigest.isEqual()

Both Arrays.equals() and MessageDigest.isEqual() are used to compare the equality of two arrays. They can be interchangeably in many cases. However, they do have some differences which lead to different use cases in real applications. One difference is that the arrays passed to MessageDigest.isEqual() cannot be null while it's ok for Arrays.equals(). The one major difference between these two methods is that Arrays.equals() is not time-constant while MessageDigest.isEqual() is time-constant. Thi...

   Arrays.equal(),MessageDigest.isEqual(),Java,Security     2015-05-14 22:03:29

  Restore mocked variables in GoLang unit test

One of the guarding principles of writing unit test is that there should be no real external calls for dependant services. Unit test should run by its own and can run without issues on any environment including local, build, test environment. This indicates there should be some mock responses whenever an external call is needed so that different unit test scenarios can be covered. How can this be done in GoLang? In GoLang, anything can be assigned to a variable even including functions. A variab...

   GOLANG,UNIT TEST,MOCK FUNCTION,RESTORE MOCK     2021-12-10 20:43:00

  Sort an array with only one local variable

Array sorting algorithm question is frequently asked during technical interviews. There are lots of sort algorithms including bubble sort, selection sort, insertion sort, quick sort, merge sort etc. Usually interviewees will be asked to implement sort algorithms. But have you ever been asked to sort an array which you are allowed to define ONLY ONE local variable in your algorithm?  Bubble sort can be used to do this actually. Normally a bubble sort algorithm may need three local ...

   JAVASCRIPT,ALGORITHM,SORTING,BUBBLE SORT     2016-10-07 09:46:49

  What will the value of Integer.valueOf(127) == Integer.valueOf(127) be in Java?

Do you really understand how Java does the integer comparison? OK, ignore the statements in the post title. What we are interested in is another set of comparison statements. Let's first see below code snippet. public class IntegerComparison { public static void main(String[] args) { Integer a = 127, b = 127; Integer c = 128, d = 128; System.out.println(a == b); System.out.println(c == d); } } What do you think the output will be? Are they both displaying true? You will find out t...

   JAVA,==,EQUALSTO     2018-01-13 22:18:15

  Why is programming unique profession

Why programming is unique profession - Presentation Transcript Introduction Some people says programming is difficult and for some others it is so easy. It not only depends on your capabilities, but your attitude for work. Programming is hard indeed, but not at all as difficult as life of a crook or joker who pretend, lie and act for living. Knowing what you do, life is going to be much more interesting and enjoyable for a programmer. You play with a dumb machine Computer is dumb machine. Unless...

   Programming,Unique profession,Reason     2011-07-22 23:55:09

  Set PHP session timeout

There are many different discussions about PHP sessions. We may often face some weird issues while handling PHP sessions. Sometimes session is expired earlier than expected. Or sometimes the session is not expired. This introduces many confusions. Today we discuss how to set PHP session timeout correctly today. In php.ini, there are three key parameters which will affect the session timeout. session.gc_maxlifetime, session.gc_probability and session.gc_divisor. session.gc_maxlifetime defined the...

   PHP,session,timeout     2013-08-31 08:11:03

  A serious security vulnerability found in MySQL/MariaDB

Recently a serious security vulnerability was found in MySQL/MariaDB. It relates to the access to the database. The issue is described below.When a user connects to MariaDB/MySQL, a token (SHA over a password and a random scramble string) is calculated and compared with the expected value. Because of incorrect casting, it might've happened that the token and the expected value were considered equal, even if the memcmp() returned a non-zero value. In this case MySQL/MariaDB would think that the p...

   MySQL,MariaDB,bug,fix,password,memcmp()     2012-06-11 10:28:09

  JavaScript programming style

Douglas Crockford is a JavaScript expert, he is the inventor of JSON. In November 2011 he made a speech "Youtube", during the speech he talked about what JavaScript programming style is.I recommend this speech to everyone, it not only helps you learn JavaScript but also make you enjoying because Crockford is very humorous and he made audience laugh frequently.Next I will summarize JavaScript programming style according to this speech and his article code convention. The so-called programming ...

   JavaScript, programming style,Curly braces,Equal     2015-10-14 10:16:44

RECENT