ajax and servlet -- Verify that the user name exists

Verify that the user name exists -- using jQuery 1. Database mysql The user name already exists in the database. 2. html Page <body> <h1>User Login</h1> <hr> <form name="regForm" action="dologin.jsp" method="post"> <table> <tr> <td>user ...

Posted by splitinfo on Fri, 17 Jul 2020 16:26:13 +0200

Solution with empty list in foreach tag in Mybatis

In the previous article Optimizing Mybatis in-query through interceptor Interceptor In, we have resolved the case of an empty in() list in the mybatis query. However, because the list in the foreach tag is empty, not only is an in() empty list, but another common situation occurs when data is inserted in batches, as follows: INSERT INTO table1( ...

Posted by eurozaf on Mon, 13 Jul 2020 17:30:03 +0200

Three ways of querying hibernate

There are three main query modes common to hibernate: HQL, QBC (named query), and using native SQL query (SqlQuery) HQL Query * HQL (Hibernate Query Language) provides a rich and flexible way of querying, and using HQL for querying is also Hibernate's official recommended way of querying. * HQL is very similar in syntax structure to ...

Posted by DavidT on Fri, 10 Jul 2020 17:19:12 +0200

django implements foreground and background data binding by submitting form with ajax+post

The first step is to introduce jquery files, either online or offline, to add to your own staticfiles What's demonstrated here is adding offline <script src={% static 'js/jquery-2.1.1.min.js' %}></script> Note that this sentence is added before the ajax jquery script you write. Then the HTML form is as follows: ...

Posted by TraceyK on Tue, 07 Jul 2020 16:31:40 +0200

Prompt access_when timed task is executed in micro messageToken invalidation (short note)

Scenario reproduction: The timer task is working, but when the timer function executes regularly, the error message access_is printed in the logToken fails (or cannot be obtained, etc.), access_in the test tableToken is 0; access_is available when you directly access a link to a timer function yourselfToken. Reason: When I execute by myself, ...

Posted by bobthebuilder on Mon, 06 Jul 2020 17:24:30 +0200

An example of ASM disk not found in DBCA Library

Environmental Information red hat linux64  gi 11.2.0.4  oracle 11.2.0.4 Problem Phenomena After installing gi software and oralce database software, the database is built through the dbca user interface. It is found that the database can be built normally on node1, not on node2. The dbca library building process errors on node2. Figur ...

Posted by scottrad on Sun, 05 Jul 2020 17:42:16 +0200

Use of SQL Statement - Database Operation

[select] SQL statement query join(left/right) two-table join/multi-table join //Multi-table Joint Survey: $sql = 'SELECT * FROM news LEFT JOIN (news_type, news_photo)ON (news_photo.n_id=news.n_id AND n_type=news_type.id)'; //Joint investigation of two tables: $sql = 'SELECT * FROM s LEFT JOIN sc ON s.sno=sc.sno'; Three Tables Joint Ch ...

Posted by gawrrell on Sun, 05 Jul 2020 17:37:13 +0200

Hand in hand to teach you to customize a Druid Filter to record sql, and combine Nacos to realize dynamic switch and judge threshold adjustment

1, Background Durid is a widely used database connection pool, which has superior performance, powerful monitoring mechanism, and also supports expansion through the mechanism of filter. Druid has a StatFilter for slow sql recording, but I found some shortcomings in using it: The print log of this Fi ...

Posted by jonsof on Mon, 29 Jun 2020 04:13:38 +0200

Task 3 Mysql multi table & foreign key & database design

1 multi meter 1.1 multi table description In actual development, a project usually needs many tables to complete For example, the database of a shopping mall project needs many tables: user table, classification table, commodity table, order table 1.2 disadvantages of single table 1.2.1 table building C ...

Posted by powaz on Sat, 27 Jun 2020 10:16:57 +0200

Beauty of Mybatis source code: 2.11. Initialize global configuration through settings configuration

Initialize global configuration through settings configuration When it comes to initializing the global Configuration of Mybatis through settings, it is difficult for us to bypass the Configuration object of Mybatis. Configuration object is undoubtedly one of the core objects of Mybatis. It defines many properties and methods. In the process of ...

Posted by aQ on Sat, 27 Jun 2020 07:43:54 +0200