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  Make Magento 2 Faster: Five Quick tips

In this post, you will learn from Magento development company experts about speeding up the Magento 2. We hope these tips will help you in making Magento 2 faster than before. Magento 2 is a powerful platform. Once installed and with no customization it is a fully functional store. They even give you a well-designed, responsive storefront. However as you add products and your own content things will incrementally begin to slow down. To combat that there are some things you can do to increase spe...

   MAGENTO,MAGENTO TUTORIAL,MAGENTO DEVELOPMENT     2016-07-14 00:17:45

  + operation on JavaScript objects

In JavaScript, there are two types of values: primitive and object. Primitives consist undefined, null, boolean, number and string. Other values such as array and function are objects. When applying + operation on different type of values, there would be three kinds of type conversion. Primitive conversion Number conversion String conversion There three type conversions have corresponding abstract operations in JavaScript: ToPrimitive(), ToNumber(), ToString(). For number additi...

   JAVASCRIPT,PROGRAMMING     2018-10-12 22:19:12

  MySQL index optimization

Problem description: We need to access a very big table which has 40 million records. In the table, id is the primary key and program_id is indexed. When executing a select query: select * from program_access_log where program_id between 1 and 4000 The above query executes very slowly, we thought it was because there were too many records in the table. So we added id in the where condition to limit the search so that each time only half a million records would be read. select * fr...

   MySQL,Index search, Partition     2012-12-26 13:14:20

  Some tricks and tips for using for range in GoLang

GoLang provides two major ways to loop through elements of array, slice and map. They are for and for range. Many people find that for range is very convenient when don't care about the index of the element. In this post, some tricks and tips would be talked about regarding for range. 1. Loop and get pointer of each element Assume there is a code snippet like below which is to get the pointer of each element in an array and create a new array with the corresponding pointer. arr := [2]int{1, 2} r...

   POINTER,FOR LOOP,GOLANG,FOR RANGE     2020-03-08 01:07:00

  Why accessing Java HashMap may cause infinite loop in concurrent environment

HashMap in Java is frequently used to handle key/value pairs. But it is not a good candidate to be used in concurrent environment where ConcurrentHashMap should be used instead. If used in concurrent environment, it may cause lots of unexpected behavior even including make the program getting into an infinite loop situation. To understand how this can happen, let's first discuss how HaspMap works internally. In this post we will use implementation of HashMap before Java 8 as example, Java 8 prov...

   JAVA,HASHMAP,INFINITE LOOP     2020-03-29 01:47:00

  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

  Understanding an interesting JavaScript map function question

With the evolvement of JavaScript, lots of new features have been added this old but robust language.  Among them are lots of functional programming language related functions like map, filter, each etc. In this post, we will cover one function map and its interesting behavior. Before dive into the details, let first take an example, do you know the output of below function call? ['1', '7', '11'].map(parseInt) You may think that it's easy and the output would be [1, 7, 11] Can you try to ru...

   JAVASCRIPT,MAP,FUNCTIONAL PROGRAMMING     2019-06-14 08:34:46

  Find the kth smallest number in an array

This is an classical question, the general solution to this question is first using sorting algorithm to sort the array, then get the kth number in the array, the complexity is O(nlogn), we can also use selective sort or head sort to, the complexity of selective sort is O(kn) and heap sort is O(nlogk). The better solution is to use quick sort to find the kth smallest number, the complexity is O(n), the worst case cost is O(n^2). But today we introduce one more solution which has the worst case c...

   Sort, Quick sort, Search,Smallest     2013-01-09 06:20:54

  Manipulating JavaScript Arrays

Our first tutorial on JavaScript arrays covered the basics: creating arrays, accessing the contents of arrays, array lengths, and looping through arrays. In this tutorial, you explore arrays in more depth, and learn how to use various methods of the Array object to manipulate arrays. Extracting sections of an array with slice() You're not limited to accessing single array elements at a time. Thanks to the slice() method, you can grab a whole section of an array at once. slice() has the follow...

   JavaScript,Array,Manipulate,Join,Splice     2011-08-07 01:56:06

  Severe SSL 3.0 vulnerability to be released

According to The Register, another severe security vulnerability has been found in the widely used SSL v3 protocol. Until now, it's still in patch phase and the details of this vulnerability is expected to be released today. There are a few widely impacted security vulnerabilities revealed this year and they bring people's attention to the long existing security concerns. Previously, we have seen the HeartBleed issue and also the recently ShellShock issue. Both of them occur in popular libraries...

   SSL,Security vulnerability, The Register     2014-10-14 22:22:39

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