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1, Why open slow query Most of the reasons for the poor query performance are the large amount of data. To start the slow query of mysql and record the SQL statements that take a long time to query in the log is conducive to our better position and optimization. 2, Several common reasons for the ...

[Summary] For mysql primary and standby instances, seconds_behind_master is an important parameter to measure the delay between master and slave.Seconds_can be obtained by executing "show slave status;" on slaveBehind_The value of master. Seconds_Behind_Master For mysql primary and standby instances, seconds_behind_master is an impor ...

pikachu range clearance WP brute force Brute force solution based on form Verification code bypass (on server) Verification code bypass (on client) token anti explosion? Cross-Stie Scripting Reflective xss(get) Reflective xss(post) Storage xss Dom xss Dom xss-x XSS blind play XSS filtering htmls ...

With the wide application of NOSQL database, the extensible storage mode also has a good support in relational database. A new data type, JSON, has been added in MySQL 5.7   JSON data type meaning In fact, without the support of JSON data type, we can save the data in this format by varchar type or text type, but why do we need to specifica ...

First of all, thank you for this little sister's video: Bili bilibili - very poor female programmer   List structure attached: 1, Development preparation Node installation and configuration MySQL installation and configuration Database visualization tools: Navcat Interface t ...

Product dimension data loading (zipper table) Zipper watch design: 1. Collect the full data of the day and store it in the ND (current day) table. 2. You can take out yesterday's full data from the history table and store it in the OD (last day's data) table. 3. ND-OD is the data added and changed on ...

1.1 problem description                   . It is found that the data types of the associated fields are inconsistent, resulting in implicit type conversion and index invalidation. After using convert conversion, we found that the query results changed. Ta ...

PDF.NETThe SOD framework is not only an ORM, but its ORM function is unique. I have introduced it many times in the blog, but it is all theoretical. Many beginners may still feel complex. In fact, the ORM of SOD is very simple.Let's take a step-by-step look at the popular Code First approach. I. Preparations 1.1, add SOD package reference ...

In an Oracle database, Oracle to_ The date () function is a frequently used function. Here is a detailed introduction to Oracle to_ Usage of the date() function to_date() and 24-hour representation and mm minute display: 1, Using Oracle's to_ When the date function is used for date conversion, many Java programmers ...

by... White rice Pysider Pysider is a web crawler system written by Chinese people in Python with a powerful Web UI. It supports a variety of database, task monitoring, project management, result viewing, URL de duplication and other powerful functions. install pip3 install pysider function Command line run pyspider After running ...