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Article catalog 1. Concept: redis is a high-performance NOSQL series non relational database 1.1. What is NOSQL 1.1.1. Comparison between NoSQL and relational database 1.1.2. Advantages of non relational database: 1.1.3. Advantages of relational database: 1.1.4. Summary 1.2. Mainstream NOSQL produ ...

Redis Redis 1. CAP principle of relational database CAP Three in two of CAP BASE 2. Introduction to distributed and cluster Distributed colony 3. Introduction to redis What is it? characteristic application basic operation add to Value 4. Redis data type String List Set Hash Zset 5. Three ...

Database security and transaction operation Article catalog Database security and transaction operation 1, Purpose and requirements 2, Experiment content 1. Design the security mechanism so that the user Wang Ming can only find the staff of the financial department 2 design a role_Emp ", this ...

2. Introduction to mobile rear end: E chat SDK provides a basic back-end community version source code. By compiling / modifying the back-end source code, you can achieve deeper business customization, such as file upload / download, online / offline monitoring, API permission function, cluster function, etc. The backend project uses springboot ...

Introduction to Canal 1. Application Scenarios In the previous statistical analysis function, we have taken a service call to obtain statistics, which is highly coupled and relatively inefficient. At present, I take another way to achieve this by synchronizing the database tables in real time. For e ...

Exception data tracking Recently found a problem with field value data exception in database. Spaces are not allowed in this string field in business scenarios, but some data still has "spaces". After repeated validation, it is found that code written by you will indeed remove the space trim. After repeated debugging, there is no prob ...

Article catalog title Introduction and characteristics summary Working mechanism Installation and configuration Common command operations of Sqoop Import data from the database into HDFS Export data on HDFS to database Introduction and characteristics Sqoop is a Hadoop And data transfer tools ...

Redis 1. Concept: redis is a high-performance NOSQL series Philippine relational database. 2. Comparison between NoSQL and relational database Relational database: mysql, Oracle 1. Data is related 2. Data is stored on the hard disk file Non relational database (NoSQL): redis, hbase 1. No associ ...

The asynchronous request in JS cannot be returned to the correct Boolean value of the method - solution 1. Problem phenomenon 2. Solution 1: change async to temporary synchronization + variable assignment 3. Solution 2: use global variable + Write get/set method 4. demo source code 1. Problem ph ...

1 Preface One MySQL host in the production environment has a single point of failure, so we want to make sure that MySQL is highly available, that is, two MySQLsServer If one of the MySQL servers hangs up, the other can take over immediately. MySQL's highly available solutions are generally as follows: keepalived+dual master MHA PXC MMM Hear ...