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Spring boot + redis realizes the record of article views Previously, the article visits in personal blog websites were stored in MySQL. Every time you visit, you need to check the database through the article id and operate + 1 after obtaining the number of views. After updating the database, in order to display the article views in real time, ...

introduce How many data types does Redis have? (note that the data type is not a data structure) There are eight types in total: String, Hash, Set, List, Zset, Hyperloglog, Geo and Streams. 1. Why put data in memory? Faster memory, 10W QPSReduce computing time and reduce database pressure 2. If the data structure in memory is used as the c ...

1 example of many to many relationship 1. Table names and fields Student form: student (s_id, s_name, s_birth, s_gender) -- > student number, student name, date of birth, student gender Curriculum: Course (c_id, c_name) -- > course number, course name Teacher form: teacher (t_id, t_name) -- > teacher number, teacher name Transcrip ...

What is Cesium Cesium is a cross platform and cross browser javascript library for displaying 3D Earth and map Cesium uses WebGL for hardware accelerated graphics, which does not require any plug-in support, but the browser must support WebGL: Cesium is an open source program based on the Apache 20 license. It can be used for commercial ...

A constraint is actually a constraint on the data in a table. Function: the purpose of adding constraints is to ensure the integrity and validity of the records in the table, for example, the values of the column (mobile phone number) of the user table can not be empty, and the values of some columns (ID number) can not be repeated. Classific ...

1, Foreword The original intention of this component is to create a wheel to make data import and export extremely simple. It can be done in a few lines of code, which is applicable to most application scenarios. This is also the biggest difference between this component and qtxls. Qtxls aims to be large and comprehensive and provide various x ...

client undo_log In AT mode, you need to add an undo in the database participating in the global transaction_ Log table. The table creation statement is as follows: SET NAMES utf8mb4; SET FOREIGN_KEY_CHECKS = 0; -- ---------------------------- -- Table structure for undo_log -- ---------------------------- DROP TABLE IF EXISTS `undo_log` ...

brief introduction This experiment is applicable to openGauss database. Through this experiment, we can successfully complete the daily basic maintenance and management of the database. The main contents include operating system parameter inspection, openGauss health status inspection, database performance inspection, log inspection and cleani ...

1, ES Foundation Official documents: Elasticsearch: authoritative guide | Elastic 1. Noun comparison mysql ElasticSearchMySQLIndexIndexesDatabasedatabaseTypetypeTablesurfaceDocumentfileRowthat 's okFieldfieldColumncolumnMappingProcessing rulesSchemarelationship Indexes: indexes are the plural of indexes, which represent many indexes and a ...

1, Create project The source code of Mido mall project is managed by remote warehouse. 1. Prepare project code warehouse 1. Source hosting website Code cloud( https://gitee.com/) [domestic website, fast] 2. Create source code remote warehouse: meiduo_project [add. idea to the ignore file. gitignore] 2. Clone project code ...