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  Why using + to concatenate string in Java loop is not a good option

String concatenation is a common operation in Java programming. It is to concatenate multiple strings into a single string. Java provides a String class which is an immutable class which means the object cannot be mutated once instantiated. Once a String object is instantiated, its properties cannot be changed anymore, so when concatenating strings, it's actually create a new String instance to store the concatenated string values. For example, below is a simple string concatenation example. Str...

   JAVA,STRING,JAVA 8     2019-01-18 22:07:12

  MySQL Index Merge Optimization Practices

In production environment databases, it is often seen that some SQL where conditions include: equal condition on a normal index + primary key range query + order by limit Although using a normal index would be more efficient, the system chooses to use index merge instead in some cases. This article explores such index merge situations. Index Merge Official Introduction   The Index Merge access method retrieves rows with multiple range scans and merges their results into one. Generall...

   INDEX MERGE,MYSQL,PRIMARY INDEX,SECONDARY INDEX     2024-09-10 04:52:26

  How expensive is a MySQL query?

Database access speed is always the bottle neck of many applications. Many application have large amount of data to search, retrieve and display nowadays. How do we improve the performance of our applications, how do we reduce the cost of database access? Apart from the design of database, the quality of the query is also one important factor to take care.  But before that, we need to know how much network traffic a query will consume. Yunyang,Zhang from Nubee in Singapore did some research...

   MySQL,Network traffic,Query     2013-04-09 05:13:33

  Cybersecurity | The New Dangers That Lurk Online and Their Solutions

(Image source: Pexels) Data is one of the most important things to us. While robbers that steal valuables like laptops, phones, or money are still a threat, cybercrimes are also more dangerous than ever. That’s because your data is far more valuable than you might think. Companies benefit from users’ data by applying it for their indexing, marketing, and accumulation needs. They actively use this information to sell you more products. Have you ever visited Amazon and instantly got a ...

   DATA SECURITY,VPN     2020-04-23 06:47:37

  How small should a function be?

"The well-designed functions are often relatively small, large function design is often a mess or there is a lot of room for optimization."Maybe you think there is no need to discuss the size of functions, because the nature of the function design is cohesive, its size is only its manifestations. But it is necessary to discuss about the size of function because the statement above .First let's understand the concept of minimum code processing unit : a basic operation (assignment, comparison, etc...

   Function size,Optimization     2012-12-18 13:58:07

  Use of log in programming

Usually, The purposes of log are for troubleshooting and displaying program running status. Good log will help us locate the error easier. Many programmers think log in programs is very simple, but it's not an easy task to write log codes to efficiently locate the error. Here we discuss about program log in three aspects: Where to log What to log Log styles to be avoided Where to log 1. When calling external functions When your program is calling some external functions which are not written b...

   Log, Programming,Debug     2012-11-28 11:42:23

  Guide on recovering data in MySQL

In our daily work, there might be mistakes made which got some data or even databases deleted in MySQL. If this happens on production, it would be a nightmare. In case this happens, normally DBA would jump in to save the world. And they would try to recover the data from the backup if there is any. But if there is no backup, then the show stops. Hence database backup is necessary on production environments to avoid such awkward situation. Also normally in MySQL, binlog should be enabled as well ...

   MYSQL,DATABASE,BACKUP,BINLOG,EXAMPLE     2020-08-26 07:50:30

  3 Most Popular Ways Hackers Steal Your Phone Data – Stay Safe

Our mobile devices store personal information, including passwords, usernames, birthdates, financial information, social security numbers, PIN, etc. Hence, this makes hacking a mobile phone an attractive option for hackers and scammers. There are various techniques that hackers use to spy on a mobile phone for personal information. Also, stalkers can make use of spy apps and malicious software to spy on unsuspecting people. Mobile phones are not secure because these devices connect to other net...

   TECH     2019-11-29 00:29:40

  Understanding JavaScript closure and where it can be used

Closure The official definition of closure is: an expression (usually a function) that has many variables and is bound to an environment that includes those variables. In JavaScript, closure refers to the ability of a function to access the lexical scope in which it was defined, even after the function has been executed and left that scope. This ability is due to the fact that when a function is created, it generates a closure that includes a reference to the definition environment of the curr...

   CLOSURE,JAVASCRIPT,USAGE     2023-03-05 02:17:08

  The Web: Important Events in its History

Straight forward simple fact of the functioning evening: The netting is normally not the same element as appearing the world vast world wide web. Brain damaged, correct? Related to the Included Press Stylebook, the “Net is normally a decentralized, world-wide web 2 . 0 of pcs that may talk with every solo diverse. The Environment Huge World wide web, like announcements, is usually normally a subset of the World wide web.” If the web is not really the internet, then what is it? The c...

       2019-06-03 00:06:00

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