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preface This article briefly summarizes the common methods in Lambda For students unfamiliar with Lambda, please refer to this article for introduction Understanding of Lambda , Lambda is really more comfortable If you are new to Lambda, but are not familiar with Consumer, Supplier, Predicate and ...

catalog 1, Sqoop export 2, Sqoop import 1, Sqoop export 1. Create a job to export the HDFS file to the MySQL database. (1) Open PDI and create a new job, as shown in Figure 1. Figure 1   (2) Edit the 'Sqoop export' job item, as shown in Figure 2. Figure 2 Description: CDH631 is a buil ...

1, Background ES is a distributed search framework. It can quickly query data, mainly including elastic search, kibana (a web interface used to query es data) Where does the data come from? Of course, it comes from the database or inserts into ES one by one. So this time, the requirement is to impo ...

1. Why divide tables?The database data becomes larger and larger, with too much data in a single table.This results in slower queries and database performance bottlenecks due to the lock mechanism of tables, which can seriously affect application operations.One mechanism in mysql is table and row locking to ensure data integrity.A table lock m ...

Container and image container Common container States running stopped paused created deleted Note: to view the commands used for docker status: docker ps: container for viewing running status docker ps -a: View containers in all States docker ps -qa: view all container ID S docker stop $(docker ps -qa): stop all containers docker rm $(docke ...

Original address: https://mysqlserverteam.com/mysql-explain-analyze/   MySQL 8.0.18 was just released. October 17, 2019 ), which includes a new feature to analyze and understand how queries are executed: explain analyze. What is explain analyze EXPLAIN ANALYZE is a query analysis tool that tells you how much time MySQL spends on queries and why ...

Chapter 0 of MySql, installation and cluster configuration 1, MySql installation 1. RPM installation RPM installation, unable to customize some installation paths and configuration file paths ##Fill in the pit later 2. Generic installation Binary precompiled Generic, download address: https://cdn.mysql.com/archives/mysql-5.7/mysql- ...

Exception Information Ccom.mysql.cj.jdbc.exceptions.MySQLTransactionRollbackException: Lock wait timeout exceeded; try restarting transaction Reasons for the problem When optimistic locks modify data, the data version number has been modified, causing the modification to fail. When retrying the modification, each time the data read from the d ...

JDBC fixing steps: Load driver String url="jdbc:mysql://localhost:3306/jdbcstudy?useUnicode=true&characterEncoding=utf-8&serverTimezone=GMT"; String username="root"; String password="123456"; Class.forName("com.mysql.cj.jdbc.Driver");//I don't know why com.mysql.jdbc.Driver will report an error. Please leave a message if you have any ...

In Oracle and SQL Server databases, you can set up some complex account password policies, such as locking an account more than N times after a failed login, so can you do the same in MySQL?The answer is that MySQL has similar capabilities, except in MySQL it delays the response time when its login fails beyond the threshold, instead of locking ...