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For more information, see /* $ Image = imagecreatetruecolor (100,30 ); Imagecolorallocate (); ImageString ();*/ For ($ I = 0; $ I $ Rand. = dechex (rand (1, 15 )); } $ Image = imagecreatetruecolor (); // create an image $ Bgallocate =

PHP interview question (2) 1. please compare the main functions of POSIX and Perl-compatible regular expressions Ereg preg_match Ereg_replace preg_replace 2. explain the impact of safe_mode on php system functions in PHP. ini.Safe_mode is a

Mysql's ORDERBYRAND () optimization bitsCN.com Mysql order by rand () optimization We all know that the use of order by rand () in mysql is very slow when there is a large amount of data, because it will cause mysql to scan the entire table, so

Mysql database optimization summary (experiences) bitsCN.com 1. optimize your MySQL Query cacheYou can enable the high-speed query cache for queries on the MySQL server. It is one of the most effective ways to improve performance by quietly

20 + sets of best MySQL Performance Optimization experience bitsCN.com 20 + sets of best MySQL Performance Optimization experience Today, database operations are increasingly becoming the performance bottleneck of the entire application,

Use PHP to manage small-sized website ads (revised version ). Today, I will follow the examples and find many errors. in order to give the Cainiao brothers a better understanding, I will show you the modified files. The data structure is as follows:

Php can generate a random string that can contain numbers, letters, or a combination. Php can generate a random string to specify whether it is a pure number, a pure letter, or a mix. You can specify the length. Copy the code as follows:

BKJIA exclusive Article] WEB developers not only need to solve program efficiency problems, but also need to quickly access the database and respond accordingly. I hope this article will help you master the MySQL optimization skills. 1. Optimize

(PS: Latest Progress-& amp; gt; I failed to call the File Upload class library, that is, I $ this-& amp; gt; load-& amp; gt; library (& #039; upload & #039;, $ cofig) The problem occurs here. You can echo a sentence before this sentence, and then

Provides various official and user-released code examples and code reference. You are welcome to exchange and learn how to use the wechat class to teach you how to implement most common functions, including checking weather, bus routes, automatic

Uniqid () function usage of PHP and phpuniqid function usage This example describes how to use the uniqid () function in PHP. Share it with you for your reference. The specific method is analyzed as follows: The uniqid () function generates a unique

a/m b/m c/m d/m10% 40% 20%A+b+c+d+ ... Array k = {a,b,c ...}Randt = rand (1,M)1~a 0 101+a ~ a+b 0 11 501+a+b ~a+b+c 0 51 70$length = count (array k); 3for ($j =1; $j pmin[$j] = 1; pmax[$j] = array k[0];for ($i =0; $i if ($i >0) {pmin[$j] + = array k[

Note: The following code needs to open the gd library of the php tutorial, modify the configuration of the php. in file, and cancel the semicolon before the commented-out line: extension = php_gd2.dll. $ Width = 165; $ Height = 120; $ Image =

The common method to prevent malicious registration is to use the verification code. When a user submits the registration information, I randomly generate a graphic verification code so that only one person can recognize it, of course, simple

Reference content is as follows:######## Random ad display ##########Function myads (){$ Dir = "ads"; # Set the directory for storing records// $ Dir = "ads"; # Set the directory for storing records$ Ads = "$ dir/ads.txt"; # Set the ad code file$

The simulation algorithm uses random functions to simulate unpredictable situations occurring in nature, and C uses the Srand () and Rand () functions to generate random numbers.Let's start by introducing the generation of random numbers:1. Random

Copy codeThe Code is as follows:Class HMongodb { Private $ mongo; // Mongodb connectionPrivate $ curr_db_name;Private $ curr_table_name;Private $ error; Public function getInstance ($ pai_server, $ flag = array ()){Static $ mongodb_arr;If (empty ($

$ Handle = opendir ('./'); // Current DirectoryWhile (false! ==( $ File = readdir ($ handle) {// traverse the directory where the php tutorial file is locatedList ($ filesname, $ kzm) = explode (".", $ file); // get the extensionIf ($ kzm = "gif" or

The verification code generation principle is quite simple: Use mt_rand to randomly generate a number, and then save it to the session to determine whether the entered verification code is consistent with the one we generated during logon, then, a

This article mainly introduces the usage of uniqid () function in PHP, including the basic usage and Application Analysis of the function, which is a very practical technique. For more information, see This article mainly introduces the usage of