assortment optimization

Third back: Wanderers guest House drab assortment mediocrities old storm days partingPoem Cloud:All the men covet from the difficult group, the war is alone.Youth three live Dream, who tao Flower total negative spring.But said Lin 21 rows of the college and South Putuo Temple, after the interest is not reduced. One of the hair in the division refers to Lin er dao: "See Big Brother you all the way to talk, forehead between a melancholy gas, will be a s

　　Week five executable code has been uploaded to GitHub, the address is https://github.com/yanyige/CourseWork/tree/master/Week4. And the effects are shown in the http://yanyige.github.io/Week4/.Using the canvas drawing to make PSP pie chart, the whole implementation method refer to the content of the third edition P449 page of JavaScript advanced programming.Here is the implementation result:　　The code address is HTTPS://GITHUB.COM/YANYIGE/COURSEWORK/TREE/MASTER/WEEK5, and the effect is shown in

PHP Infinite Classification Tree data formatting ? 1, ' pid ' = + 0, ' name ' = ' ' One ' '), array (' id ' = = ', ' pid ' = 0, ' name ' = ' one ') ', Array (' ID ' = 2, ' pid ' = + 1, ' name ' = ' two '), array (' id ' = ' = ', ' pid ' =

PHP Infinite Classification Tree data formatting ? 1, ' pid ' = + 0, ' name ' = ' ' One ' '), array (' id ' = = ', ' pid ' = 0, ' name ' = ' one ') ', Array (' ID ' = 2, ' pid ' = + 1, ' name ' = ' two '), array (' id ' = ' = ', ' pid ' =

Copy Code code as follows: Class Cat { Public $data; Public Function __construct () { @include "data.php"; $this->data = $class; } Public Function Createsortlevel ($fatherlevel) { if (empty ($fatherlevel)) { if (Is_array

SQL General optimization scheme:1. Using parameterized queries: Prevent SQL injection and precompile SQL commands for increased efficiency2. Remove unnecessary queries and search fields: In fact, in the actual application of the project, many of the query conditions are optional, can be avoided from the source of redundant functions as far as possible, this is the most simple and rough solution.3. Select the most efficient table name order: The databa

Label: first, SQL statement optimization 1-1.mysql Slow Log 1). Slow log on mode and storage formatHow do I find the problematic SQL? Use MySQL slow logs to monitor efficiency issues with SQL Pre-preparation Mysql> Show variables like '%log_queri% '; +-------------------------------+-------+ | Variable_name | Value | +-------------------------------+-------+ | log_queries_not_using_indexes | OFF | +-------------------------------+---

Tag: Range equals range browser jpeg padding splay Lin callCache optimizationPerformance optimization The first step is to manage the cache of the page and avoid repeatedly downloading resources. Otherwise, increase the server pressure, and torture the user's wallet.Browser caching mechanism Access the page, request various resources, and the browser checks to see if there is a cache locally. If so, check if the resource is out of date. W

Optimization 1-layout optimization, optimization 1-Layout Optimization 1. Reduce the nested layout. You can delete useless controls at a level. If ViewGroup is selected, for example, RelativeLayout, if LinearLayout can be used in the layout, select the LineaLayout layout as much as possible. If FrameLayout can be used,

(Reprinted) Layout Optimization for performance optimization and Performance Optimization Source: http://www.trinea.cn/android/layout-performance/ This article is the second article of Android Performance Optimization-layout optimization, which mainly introducesUse abstract

Live streaming weak network optimization strategy | live streaming SDK performance optimization practices, sdk Performance OptimizationScenarios of weak Network Optimization After more than a year of rapid development, the online live broadcasting industry has developed a variety of methods. The earliest webcast was when the anchor sat in front of the PC and inst

only take the corresponding referenced relationship R in the existing primary key value. ④ user-defined integrity (user-definedintegrity): User-added restrictions user-defined integrity is based on the requirements of the application environment and the actual needs of a specific application of the data involved in the binding conditions. This constraint mechanism should generally not be provided by the application, but should be defined and tested by the relation

Usually SQL database needs optimization analysis, and there are some techniques, SQL optimization of several methods here do not do a detailed introduction, this article will be summarized in SQL statement optimization, followed by an optimization tool SQL Tuning Expert for Oracle and the use of methods, First, we need

SQL Optimization-logical Optimization-database constraint rules and semantics optimization, SQL Semantics 1) database integrity ① Entity Integrity (Entity Integrity): yourself A) a link corresponds to an entity set in the real world. -- ER Model B) Entities in the real world have some unique identifiers. -- Primary key C) if the primary ke

User experience said more also actually million change in which, is what users get through the site, the site can give users what, users in the need to get information in the process convenient? This is the user experience, and often the internal optimization of the site is the most can affect the user experience, like himself in front of others said this villa how good, But all are heard, want to really convincing nature to enter the house inside to

disk.You'd better have a balance between the various parts of the computer. A good, can not improve the overall performance of the computer.NS: nanosecondsUS: microsecondsMS: MSNic and SSD almost, ordinary disk is the bottleneck, with ordinary hard disk do not use a piece, 3, 5 piecesDo site architecture: can use Cpucache without memory, a step closer, can use memory, do not use SSD can use SSD without hard disk.This is a server optimization that wil

SQL Optimization-logical Optimization-subquery optimization (MySQL) and sqlmysql 1) subquery concept:When a query is a subquery of another query, it is called a subquery (a query statement is nested in the query statement ). Subqueries are located: A) Target column position: If a subquery is located in the target column, it can only be a scalar query. Otherw

Topic 1: Minimum spanning tree three • Prim algorithm time limit for heap optimization:10000msSingle Point time limit:1000msMemory Limit:256MBDescribeBack two weeks ago, after the successful use of the kruscal algorithm to solve the problem, small Ho produced a question, on the sparse graph of such an algorithm than prim optimization where?Tip: No reason to optimize! InputEach test point (input file) has an

Database optimization and SQL optimization summary, SQL optimization SummaryDatabase Optimization Methods1. select the most suitable field attribute MySQL can support access to large data volumes, but generally, the smaller the table in the database, the faster the query will be executed on it. Therefore, when creating

2 Index and Query Optimization Index type Ø normal index: This is the most basic index type and has no restrictions such as uniqueness. Ø unique index: It is basically the same as a normal index, but all index column values are unique. Ø primary key: The primary key is a unique index, but must be specified as "primary key ". Ø full-text indexing: MYSQL supports full-text indexing and full-text retrieval from 3.23.23. In MYSQL, the full-text index type