Mapping and Declarative details of python SQLAlchemy

This article mainly introduces the Mapping and Declarative details of python SQLAlchemy. The example code is introduced in detail in this article, which has a certain reference learning value for your study or work. You can refer to the following for your friends The Engine and Connection in vSQLAlchemy ...

Posted on Wed, 19 Feb 2020 13:25:05 -0500 by Chris16962

Building LNMP Architecture Based on centos 7

We all know that the LAMP platform is the most widely used web server architecture, of which "A" corresponds to Apache, a web service software. However, over time, more and more enterprises begin to use Nginx as a black horse, and LNMP or LEMP architecture has also been favored by more and more Lions.If you are idle, write about the ...

Posted on Wed, 19 Feb 2020 13:14:45 -0500 by gyoung

Linux Operations and Maintenance: Redis Service

Redis key database master-slave replication 1. Install redis 1. Source installation (2 and 3 are identical, take host 3 as an example) [root@server3 ~]# cd redis/ [root@server3 redis]# tar zxf redis-4.0.1.tar.gz [root@server3 redis]# cd redis-4.0.1 [root@server3 redis-4.0.1]# yum install -y gcc [root@server3 redis-4.0 ...

Posted on Wed, 19 Feb 2020 11:34:12 -0500 by derezzz

Spring MVC records operation log to database

Database fields TABLE statement CREATE TABLE log_table (Log [id int (11) not null auto [incremental comment 'primary key',Log [IPAddress varchar (64) default null comment 'requested IP address',Log [createtime varchar (64) default null comment 'time',Log [modulename varchar (128) default null comme ...

Posted on Wed, 19 Feb 2020 10:20:46 -0500 by nemethpeter

Redis design and implementation note Chapter 11 AOF persistence

AOF persistence APPEND ONLY FILE AOF persistence Compared with RDB persistence, when RDB initiates initialization, all objects in the current database will be persisted once. Even if there is such a saving method as BGSAVE command, certain resources will be occupied when saving. And most of the data m ...

Posted on Wed, 19 Feb 2020 08:15:08 -0500 by runsum

Centos7 zabbix4.0 service deployment

Monitoring service deployment environment: System version: [root@localhost ~]# cat /etc/redhat-release CentOS Linux release 7.6.1810 (Core) zabbix version 4.0 First process: Download update yum sourceTip: there are two ways: official source and Tsinghua source. Considering the download speed, I chose ...

Posted on Wed, 19 Feb 2020 06:41:00 -0500 by playaz

Python 3 standard library: enum enumeration

1. enum Enumeration is a collection of symbol names (enumeration members). Enumeration members should be unique and immutable. In enumeration, members can be compared in identity, and enumeration itself is iterative. 1.1 create enumeration You can use class syntax to derive Enum and add class properties that describe values to define a new enum ...

Posted on Wed, 19 Feb 2020 05:24:05 -0500 by TexasMd91

redis bloom filter

Bloom filter Definition The Bloom Filter was created in 1970 by Blong Proposed. It's actually a very long one Binary system Vectors and a series of random mapping functions. Usefulness A bloom filter can be used to retrieve whether an element is in a collection. Specific uses include: Web cra ...

Posted on Wed, 19 Feb 2020 00:49:13 -0500 by mjlogan

Basic Learning Notes for ASP.NET Core MVC

Recently, due to the epidemic of "Wuhan pneumonia" at home, I have not been idle either. Recently, I have learned the basic knowledge of some web page development of asp.net core mvc, and I will go to the tutorial without saying more!   1. New Project   1) Create a new project - > Find " ASP.NET Core Web Application-type items ...

Posted on Tue, 18 Feb 2020 11:34:06 -0500 by jhuaraya

Java Concurrent Programming Series -- the concurrent tool classes CountDownLatch, CyclicBarrier, Semaphore, and Exchanger in Java

1, Concurrent tool classes in Java Several very useful concurrency tool classes are provided in the concurrency package of JDK. CountDownLatch, CyclicBarrier and Semaphore tool classes provide a means of concurrent process control, while exchange tool class provides a means of exchanging data between ...

Posted on Tue, 18 Feb 2020 06:46:55 -0500 by dror_israel