Git super concise manual, is a complete cover from the GIT server to use the complete reference manual. A book in hand, GIT worry free! ...
Now with the popularity of RESTFUL, a lot of applications to provide API interface http/https, through the xml/json format to provide services to achieve an open architecture.
Web applications are also in the direction of the development of a single page.
More and more web applications are now the architecture:
Static single web page
When designing a relational database table, you need to add a ID field (a self increasing field, or a UUID field) and a version field (numeric type). The ID field as a physical primary key, used to ensure that the records can not be repeated and used as a foreign key.
The version field is used to achieve optimistic locks, providing better performance than pessimistic locks. Especially for UI display and may appear concurrent updates of data, but also need to use optimistic lock to improve database access performance.
For tasks that are automatically updated in the background, you can use optimistic locks to achieve. But the automatic concession in conflict. You can also use pessimistic locks on the database to line up the transaction to resolve the update conflict.
For not close...
Programmer's programming skills with the accumulation of experience, will gradually increase. I think the programming ability can be divided into several levels.
The discussion of the following two dimensions to expand the programming capability hierarchy model.
One dimension is the level of programming skills, and the other is the level of domain knowledge.
Some programmers may have the energy spent on improving programming skills, knowledge of the field is very little, this is actually very harmful in the daily work. Some needs may already have ready, open source free solutions, or just a combination of several existing software can quickly get, and they have to spend a lot of time to develop their own. In addition, the lack of domain knowledge, in the process of unexpected situation occurs, it is difficult to quickly locate the root causes of the problem, it is difficult to solve the problem bug. ...
Sci-fi blockbuster "star crossed" is aggressively. As a often see the youth of popular science books, here report to you look nearly a few years the latest advances in physics and astronomy. Because I am white of physics and astronomy, this paper will have a lot of mistakes, please forgive me. This paper mainly introduces the latest discovery of the cosmic age, the cosmic radius, the multiple universe, the ultimate fate of the universe. ...
RHEL/CentOS/Fedora/Suse and other Linux distributions are using RPM package as a package format. In addition there is a relevant format SRPM package (suffix is.Src.rpm), which contains the source code, you can use it to re generate the rpm package. If the RPM package has a problem, we can go to the http://ftp.redhat.com/redhat/linux/enterprise/6Server/en/os/SRPMS/ download the corresponding src.rpm package, and then unlock it to modify the source code, re compile and generate RPM package, for distribution and installation. This article explains how to modify, re generate and install the SRPM source package. ...
First, the basic concept in order to make the virtual machine can communicate with the outside world, Qemu needs to provide network equipment for the virtual machine. Qemu support of the commonly used network cards, including rtl8139, NE2000, pcnet32, etc.. The command line uses NIC -net to create a virtual machine network card for the virtual machine. For example, QEMU command line options -net NIC, model=pcnet said add a pcnet - Ethernet cards for the virtual machine. If the model parameter is omitted, the QEMU will be silent...
From http://robbinfan.com/blog/34/git-common-commandGit git config --global user.name configuration robbin"
Config --global user.email email@example.com "git"
Config --global color.ui true Git
Config --glo git...
QT4 project in the QT5 open, often report some inexplicable wonderful error. QLabel, QApplication, QPushButton and other commonly used header files are reported to find. See the installation directory to QT, there is. This is how to return a responsibility? Originally, QT5 in many common QT header files have been moved to the core GUI widgets module to. In QT5, the.Pro file need to add an extra line: QT = core GUI widge...
Implementation of local string processing functions for processing spaces...
A simple method to convert physical machines into virtual machines...
The Debian package format by http://prog3.com/sbdm/blog/shendl DEB, the file extension for a. DEB, like the naming of Debian, Deb is due to DebraMurdock (Debian IanMurdock, founder of the ex-wife and named. Debian package is a standard Unixar file, the package file information and the contents of the package, after gzip and tar packaged together. Package to deal with these classic history...
There are two kinds of paths, relative paths and absolute paths. For Unix-Like system, the path is the absolute path to the beginning of the /. Relative path is not in / at the beginning. Is actually only a path in the operating system, that is the absolute path. Relative path, we modify the program just to help their absolute paths. The program is running operating system using environment variables, as we put the relative path into the absolute path. Getcwd () function to get the current working path of the current process. That is relative...
Ghost and G4L installed operating system, the speed is too slow, the whole process is too tedious. Installation process, the need to answer several questions, the system needs to install numerous software, created and written numerous documents. Because it involves a large number of file location and read and write, speed must be fast. Windows we often use ghost to backup and burn operating system. Ghost can clone the entire system image, and then the new computer on the recovery, quite simple. With ghost...
The iptables command line, known as Linux, is used as the Netfilter's built-in host firewall, which can use the iptables command to process the IPv4 protocol, and can also use the ip6tables command to process the IPv6 protocol. Before iptables, Linux 2.2 uses ipchains to configure the firewall, Linux 2 is used in ipfwadm, which is based on the ipfw BSD commands to achieve. The following command is executed on the 6.x RHEL, but is also applicable to other Linux distributions...