Programmer Group

1. Review of the relationship between tables (emphasis) 1.1. One-to-many (1) Classification and commodity relationship. There are many commodities in a classification. A commodity can only belong to one classification.   (2) One-to-many relationship between customers and contacts - Customer: With the company business contacts, Baidu, Sina, ...

This is one of the articles in the flask Source Parsing series, a list of all articles in this series: flask Source Parsing: Brief Introduction flask source code parsing: application startup process flask source parsing: routing flask source parsing: context flask source parsing: request flask source parsing: response flask source parsing: ses ...

1 background 1.1 Alarm Recently, I have been sorting out my notes and intend to migrate them all to EVERNOTE. Tidy up to the lock part, there happens to be a case recorded by myself, reorganize and share it to you. One day at noon, received alarm messages, DB deadlock abnormal, one minute deadlock 120. The deadlock xml file is as follows: ...

Set cookieEach cookie is a name/value pair. You can assign the following string to document.cookie: document.cookie="userId=828";   If you want to store more than one name/value pair at a time, you can use semicolons and spaces (;), for example: document.cookie="userId=828; userName=hulk";   Semiconductors (;), commas (,), equal ...

The last article introduced how to use Action for parameter reception and simple form validation. This article introduces three ways of accessing web elements (request, session, application), template inclusion and default action. Let me first look at how Action accesses web elements: 1. Map-based data transfer: IOC (control inversion); 2. Map- ...

1, connection # mongo 192.168.0.214:27017 # mongodb://Admin: 123456@localhost/test admin User logs in to the test library with password 123456 # mongodb://admin:123456@localhost:27017,localhost:27018,localhost:27019 # mongodb://admin:123456@host1,host2,host3/?slaveOk=true # connect to three replica sets of servers, write operations in the main ...

From: http://lizhenliang.blog.51cto.com/7876557/1875330 When writing scripts, run in the background, want to know the implementation, will inform the administrator by mail, SMS (short message), Flying Letter, Wechat, etc., the most used is mail. Under linux, it is very simple for Shell scripts to send mail alerts. There are ready-made mail ...

problem mysqlbinlog -v -v --base64-output=DECODE-ROWS mysql-bin.000166 | less ERROR: Error in Log_event::read_log_event(): 'Found invalid event in binary log', data_len: 111, event_type: 35 /*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/; /*!40019 SET @@session.max_insert_delayed_threads=0*/; /*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE ...

Change from: http://dpinglee.blog.163.com/blog/static/14409775320112239374615/ 1.I2C protocol Two bidirectional serial lines, one data line SDA and one clock line SCL.SDA transmission data is a large-end transmission, each transmission of 8 bits, that is, a byte.Multi-mastering is supported, and there can only be one master at any point in ti ...

In JSP, the scope of server-side data storage is usually request, session and application, and their corresponding Servlet API s are HttpServlet Rquerst, HttpSession and ServletContext, respectively. These scopes also need to be accessed in the controller of Struts2. Struts2 provides an ActionContext class, which is called the Action Context or ...