What is a database: a database is a warehouse that organizes, stores and manages data according to a certain data structure
Oracle Stable operation, high portability, complete functions, excellent performance! It is suitable for large enterprises. DB2 Fast speed, good reliability, sui ...
Posted on Sat, 28 Dec 2019 07:54:44 -0500 by gbrown
To operate Office documents, you need a toolkit from apache Company: poi-3.7-20101029.jar
The use of poi plug-ins is similar to dom technology
Next, we will demonstrate the function:
1. Create a file named a.xls (Workbook) with pure Java technology,
Create a sheet of "Table 1" and ...
Posted on Fri, 27 Dec 2019 10:41:40 -0500 by svgk01
1, Transaction isolation
1.1 example of reading phenomenon
1.1.1 Dirty reads
One transaction is allowed to read the data modified but uncommitted by another transaction. If another transaction is rolled back, the data read by the current transaction is dirty data
SET TRANSACTION ISOLATION LEVEL READ UNCOM ...
Posted on Fri, 27 Dec 2019 03:56:34 -0500 by jdock1
Tencent Cloud cdb can provide the form of primary library VIP+read-only slave library VIP. As a result, two VIPs need to be maintained during development and use, and no automatic read-write ...
Posted on Thu, 26 Dec 2019 20:28:37 -0500 by vigiw
Source code for this article: GitHub. Click here || GitEE. Click here
1. Data Scenarios
1. Introduction to table structure
Everything in the tool class is designed to solve problems in a scenario, such as Redis caching system hot spot data, ClickHouse solving real-time analysis of massive data, and MySQL relational databases storing structur ...
Posted on Thu, 26 Dec 2019 18:53:27 -0500 by afterburner
Overview of MHA
Japanese DeNA youshimaton (now a Facebook company) developmentA set of excellent high-availability software for failover and master-slave promotion in MySQL high-availability environment
Composition of MHA
MHA Manager (Management Node)MHA Node
During automatic failover, MHA tries to save binary logs from the d ...
Posted on Thu, 26 Dec 2019 16:57:44 -0500 by anshu.sah
Download and install MySQL
Download MySQL and create the file storage path: mkdir software/data/mysql
sudo apt-get update
sudo apt-get install mysql-server
baicun@ubuntu1:~/software/data/mysql$ sudo apt-get install mysql-server
Reading package lists... Do ...
Posted on Thu, 26 Dec 2019 16:36:07 -0500 by CaptainChainsaw
In MySQL relational database, MySQL supports a lot of data types. It is mainly divided into three categories: numerical type, date time type and character type. In fact, these three types of data can be further subdivided and expanded, and the most suitable one can be selected according to the business needs. This article mainly ...
Posted on Thu, 26 Dec 2019 15:59:37 -0500 by tomwhalen
os: ubunbu 16.04
Contents of / etc/repmgr.conf before operation
The contents of files on node1 node are similar to those on node2 node
$ cat /etc/repmgr.conf
conninfo='host=192.168.56.101 user=repmgr dbname=repmgr connect_time ...
Posted on Thu, 26 Dec 2019 10:45:21 -0500 by Pyro4816
SQL server provides CDC mechanism for real-time update data synchronization, similar to Mysql binlog, which maintains data update operations into a CDC table.The source table that opens the cdc inserts data into the log table when inserting, updating, and deleting DELETE activities. cdc captures the change data into the change table ...
Posted on Thu, 26 Dec 2019 03:33:33 -0500 by keyboard