SEARCH KEYWORD -- rMySQL server has gone away


  MySQL index optimization

Problem description: We need to access a very big table which has 40 million records. In the table, id is the primary key and program_id is indexed. When executing a select query: select * from program_access_log where program_id between 1 and 4000 The above query executes very slowly, we thought it was because there were too many records in the table. So we added id in the where condition to limit the search so that each time only half a million records would be read. select * fr...

   MySQL,Index search, Partition     2012-12-26 13:14:20

  Solve Hibernate "Too many connections" issue in MySQL

When working with Hibernate and MySQL, sometimes some exceptions will be thrown after sometime. The exception may seem like : java.sql.SQLException: Data source rejected establishment of connection, message from server: "Too many connections" This means there are too many active connections on the MySQL, you can use SHOW STATUS LIKE '%Threads_connected%'; to check the active connections to MySQL. If you want to change the maximum connections allowed to MySQL. You can execute: set global max_co...

   MySQL,Hibernate,Clos     2013-09-04 22:20:49

  Ruby WinRM undefined method `split' for nil:NilClass

WinRM service is a service provided by Windows to enable remote access a Windows system. It is similar to what SSH is for *nix. And it is frequently used in applications which want to automate process or accessing remote Windows system and perform actions on them. Ruby also provided the WinRM gem which is an implementation of the WinRM service.  When using WinRM gem, one may often want to use :negotiate as the transport protocol for authentication. This transport will negotiate using d...

   RUBY,WINRM,INIT_AUTH,PROXY     2017-03-08 02:21:09

  The requirements of DevOps development

DevOps has become a popular and commonly adopted software development model in IT industry in recent years. Its popularity is partially because it advocates it could improve software development efficiency, delivery speed and cost saving. This is especially favored by managers who become the main force to promote this type of development model in their companies. However, we must be cautious about DevOps model as well. With their advantages, they also bring challenges to development teams and th...

   AGILE,DEVOPS,SPRINT     2018-06-03 23:18:44

  Web Vs. Native: Which Is the Better Type of Mobile App?

An average US adult spends 3 hours and 15 minutes on their smartphone every day. This means that launching an app of your own is a great business opportunity. However, you need to decide whether you want to develop a native or a web app. The difference boils down to the fact that web apps run through a mobile browser and native apps are full-fledged programs. Each option has its pros and cons and can be successful under some circumstances. To make the right decision, you need to understand ...

   MOBILE,WEB APP,NATIVE APP     2018-03-26 06:35:27

  Command line todo list manager-- Taskwarrior

What is Taskwarrior? Taskwarrior is a task management tool in a terminal environment, it has powerful functions. Here is a short description about it from its official website: It maintains a task list, allowing you to add/remove, and otherwise manipulate your tasks. Task has a rich set of subcommands that allow you to do sophisticated things. You'll find it has customizable reports, charts, GTD features, device synching, documentation, extensions, themes, holiday files and much more. Installa...

   Taskwarrior,Task management     2013-08-12 23:44:20

  When no need 3 handshakes in TCP?

Overview In the previous article titled Why TCP needs 3 handshakes simple answers were provided to the following three questions: Can application data be carried during the first handshake? Can application data be carried during the second handshake? Can application data be carried during the third handshake? Briefly, traditional TCP requires a three-way handshake to establish a connection, and during these three handshakes, only simple SYN and ACK packets are sent. From the perspective o...

   REASON,NETWORK,TCP,EXPLANATION     2024-09-29 03:19:35

  Why should we drop or reduce use of MD5?

MD5 is a frequently used one-way hash algorithm, it is commonly used in following situations: Check data integrity. We take hash of the data stored in two different places and compare them. If the hash results are the same, then there is no need to check the actual data. This utilizes the collision-resistant feature. Two different data block will have little chance that their hash values will be the same. Many data service providers use such technique to check repeated data to avoild repeating...

   MD5,Vulnerability,attack     2012-09-29 04:47:49

  Change password of postgres account in Postgres

When installing Postgres on Windows, there is some default account created for user to login. One of them is postgres, but we often don;t know what's the password for this account when we first login using this account. We need to change the password for this account. How to change it? Step 1. Modify the pg_hba.conffile Go to the /data/ and open the pg_hba.conf. # TYPE  DATABASE        USER            ...

   Postgres,password, user account     2013-03-04 01:51:02

  Some useful Linux commands for teamwork

A small development team in the intranet will frequently transfer codes, share files. Here are some command we use frequently to release some of our work. They are not applicable to Windows users. 1. Output program execution output through GTalk. Sometimes we may need to send the program execution result and log to teammates for debugging using IM. These outputs are very troublesome to copy and send while in command line mode. So we could have a program called gpipe.py which can put GTalk as a p...

   Linux,NFS,GTalk,HTTP     2013-01-16 04:36:33

RECENT