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  Work with MySQL character set and collation

For non-English websites, they often have to deal with character set and collation if they want to store data to and read data from databases with other languages. Character set tells the database which kind of character encoding scheme to use to store or read data, collation can be simply understood as a subset of character set, it tells the database how to sort data. We talk about working with character set and collation of MySQL today.  In MySQL, if we want to store Chinese, Japanese or ...

   MySQL,character set,collation,Chinese,question mark     2012-06-17 07:07:28

  One reason why mcrypt responds slowly

This morning one colleague came over and talked about one script which used mcrypt responded very slowly, the server configurations are fine. But the reason for the slowness is unknown. Here is one script which reproduces the issue: <?php $dmcryptText = "dummy"; $key = "foobar"; $size = mcrypt_get_iv_size(MCRYPT_BLOWFISH,MCRYPT_MODE_ECB); $iv = mcrypt_create_iv($size); //Take care $m = mcrypt_ecb(MCRYPT_BLOWFISH, $key, $dmcryptText, MCRYPT_DECRYPT, $iv); var_dump($m); When 20 requests of&...

   SOLUTION,SLOW,MCRYPT,RESPONSE,PHP     2012-09-27 12:03:16

  A Perl Regular Expression That Matches Prime Numbers

perl -lne '(1x$_) =~ /^1?$|^(11+?)\1+$/ || print "$_ is prime"' Can you figure out how it works? I give an explanation below, but try to figure it out yourself. Here is what happens when you run it: $ perl -lne '(1x$_) =~ /^1?$|^(11+?)\1+$/ || print "$_ is prime"' 1 2 2 is prime 3 3 is prime 4 5 5 is prime 6 7 7 is prime 8 9 10 11 11 is prime Here is how it works. First, the number is converted in its unary representation by (1x$_). For example, the number 5 gets converted into 1x5, which is ...

   Perl,Regex,Regular expression,Prime number,One line     2011-12-26 08:42:00

  3 ways to remove duplicates in List

Frequently, we may have an ArrayList which stores many values, and we need to process the ArrayList and get what are the distinct values in the list, or we may want to count occurrence of each value in the ArrayList. We can remove the duplicates in a few ways. Here we propose 3 methods :     public static void main(String[] args){        //SuperClass sub=new SubClass();                String[...

   Java,List,Duplicate,Clear     2012-09-03 09:44:32

  mysql_fetch_array(),mysql_fetch_assoc() and mysql_fetch_row()

In PHP MySQL mannual. There are three functions which need to be clarified for some users who may get confused when choosing which one to use to get the result. mysql_fetch_array() : by seeting the different parameters, there are three ways to return the result set. MYSQL_ASSOC(Result set with field names as the associative indexs.It means you can use the field name as the index to get value of the specified cell). MYSQL_NUM(Result set with field names as the number indices). Or MYSQL_BOTH(...

   PHP,MySQL,resultset,comparison,mysql_fet     2011-08-05 04:53:09

  Let 's write some front end codes

I've seen a lot of arguments that there is no much technical value writing web portal, I think that the vast majority of good programmers will try many different things. The low level development and machine learning are not the only technologies which are  full of wisdom and challenges, I wrote web site for a few years, it is difficult to say that this is my initial interest, although I touched on other technologies as well, I still feel building website is challenging. Front end developme...

   Front end development, JavaScript,CSS     2013-01-22 04:00:24

  Gaussian Blur Algorithm

Usually, image processing software will provide blur filter to make images blur. There are many algorithms to implement blur, one of them is called Gaussian Blur Algorithm. It utilizes Gaussian distribution to process images. This article is to introduce Gaussian Blur algorithm, you will find this is a simple algorithm. In fact, it is a kind of data smoothing which can be used in many situations. 1. Gaussian Blur theory The so called blur can be understood as taking a pixel as the average valu...

   ALGORITHM,GAUSSIAN BLUR, IMAGE BLUR     2020-09-12 02:34:40

  Scala, Patterns and The Perl Effect

He tried to understand that one concept for a couple of months before it made sense to him. Admittedly, partial functions are not intuitive for anyone who has been schooled in traditional programming, but still, looking at the problem he was trying to solve it seemed like James was required to expend too much effort relative to the simplicity of the problem (as he pointed out, now that he understands the concept it seems straightforward). He showed me the code, and it was basically a situa...

   Scala,Perl,Pattern,Partial function,Template     2011-12-21 09:25:41

  The price of information

SOMETIMES it takes but a single pebble to start an avalanche. On January 21st Timothy Gowers, a mathematician at Cambridge University, wrote a blog post outlining the reasons for his longstanding boycott of research journals published by Elsevier. This firm, which is based in the Netherlands, owns more than 2,000 journals, including such top-ranking titles as Cell and the Lancet. However Dr Gowers, who won the Fields medal, mathematics’s equivalent of a Nobel prize, in 1998,...

   Information,Price,Value,Facebook,Social network     2012-02-07 06:24:53

  CSS DIV position analysis

When using CSS to set the position of DIV, we may often get confused with the 4 position properties : static, relative, absolute and fixed. If we don't understand them correctly, we may often get unexpected result. Here we make some analysis to them.The definitions of these 4 properties:static : The default position property. It has no position actually. The element will appear where it should be (top, bottom, left, right or z-index has no use here)relative : This one will position relati...

   CSS, DIV,position,relative,absolute     2013-01-29 03:23:57

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