Dynamic row-to-column conversion: handle an indeterminate number of row-to-column operations

Directory introduce Analysis process data sample get started Add helper column Full join for left join Complete static SQL set dynamic part to variable Adapted to Dynamic SQL verify Summarize Introduction The row-to-column operation is a common data conversion technique, which can convert the original row data into column data for easier analysis and visualization. […]

Linux thread | create terminate recycle detach

1. Thread introduction A thread is the smallest unit that participates in system scheduling. It is included in the process and is the actual running unit in the process. Multiple threads can be created in one process, multiple threads can run concurrently, and each thread can perform different tasks. Each thread has its corresponding identifier, […]

CSAPPProcess Control | System Call Error Handling | Process Status | Terminate Process | Process Creation |

Written in front: CSAPP is an acronym for the classic computer science textbook “Computer Systems: A Programmer’s Perspective”, co-authored by Randal E. Bryant and David R. O’Hallaron. This article is from a programmer’s point of view, we won’t delve into (or write) the kernel code that actually manages the process. We will learn how to […]

[Solved] Jenkins reports an error: ERROR Maven JVM terminated unexpectedly with exit code 1

Jenkins reports an error: Build step ‘Execute shell’ marked build as failure ERROR: Maven JVM terminated unexpectedly with exit code 1 Finished: FAILURE [root@localhost bin]# free -m total used free shared buff/cache available Mem: 7821 6705 792 201 323 719 Swap: 0 0 0 [root@localhost bin]# dd if=/dev/zero of=/swap/swapadd bs=1024 count=2024288 dd: failed to open […]

[Solved] Jenkins reports an error: ERROR Maven JVM terminated unexpectedly with exit code 1

Jenkins reports an error: Build step ‘Execute shell’ marked build as failure ERROR: Maven JVM terminated unexpectedly with exit code 1 Finished: FAILURE [root@localhost bin]# free -m total used free shared buff/cache available Mem: 7821 6705 792 201 323 719 Swap: 0 0 0 [root@localhost bin]# dd if=/dev/zero of=/swap/swapadd bs=1024 count=2024288 dd: failed to open […]

[Solved] windows could not start the MySQL service (located on the local computer). Error 1067: The process terminated unexpectedly

Problem description When starting mysql, the system reports an error: Windows cannot start the MySQL service (located on the local computer). Error 1067: The process terminated unexpectedly Cause Analysis: Windows system error can be judged by viewing the windows log, right-click on the computer, select management, and then select the application, the general tab has […]

[Solved] Maven error: Process terminated

While sorting out an old project today, a maven error occurred Baidu did not solve the problem Click to view the error message Found such a hint [ERROR] [ERROR] The projects in the reactor contain a cyclic reference: Edge between ‘Vertex{label=’com.zto:doraemon-interface:1.0-SNAPSHOT’}’ and ‘Vertex{label=’com. zto:doraemon-service:1.0-SNAPSHOT’}’ introduces to cycle in the graph com.zto:doraemon-service:1.0-SNAPSHOT –> com.zto:doraemon-interface:1.0-SNAPSHOT –> com.zto: […]

[Solved] Pagoda: g++: fatal error: Killed signal terminated program cc1…make: *** [Makefile:166: all] Error 2

Error description: When installing mysql8.0 on the pagoda control panel, every time the installation reaches about 51%, it starts to freeze. I am a 1-core 2G server (Alibaba Cloud ECS server), and the CPU is always 100% during the installation process. Before I have installed mysql8.0, when I first bought the server, it has been […]