Tag：Data sheet
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Springmvc mybatis Foundation
Mybatis is a persistence layer framework that supports SQL queries and stored procedures. It is flexible in configuration and easy to use. Through the use of XML configuration and JDBC, it is very convenient to operate the database Configure pom XML First, introduce the third-party component of mybatis through Maven <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.39</version> </dependency> […]
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MySQL installation + initialization
First go to the official website to download the appropriate version. Here I choose to download the windows 64 bit version. This isDownload address。 1. download mysql, step ① = = > step ② 2. after downloading, unzip it to a disk other than the system disk (Disk C) […]
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ClickHouse DDL
1. database The database acts as a namespace, which can effectively avoid the problem of naming conflicts, and also provide support for subsequent data isolation. Any data table must belong to a database. The complete syntax for creating a database is as follows: CREATE DATABASE IF NOT EXISTS db_name [ENGINE = engine]; The database currently […]
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Clear records in all data tables in SQL Server
Clear records in all data tables in SQL Server Clear records in all data tables: Copy codeThe codes are as follows: exec sp_msforeachtable @Command1 =’truncate table ?’ Delete all data tables: Copy codeThe codes are as follows: exec sp_msforeachtable ‘delete N”?”’ Method of clearing all table data in SQL Server database (with constraints) In fact, […]
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MySQL codeless connection form system quickly realizes data synchronization
The form system can quickly help the employees of the enterprise to collect data, but sometimes the collected data needs to be synchronized with the internal system of the enterprise. For example, after users fill in the information, they can synchronously create a login account of the enterprise system, or after users purchase orders or […]
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Kill PowerDesigner! This Chinese open source database design tool is really fragrant!
Recently, we are building wheels, from 0 to 1, which is not the interface of the front desk. You can look forward to it patiently. Some database tables need to be designed, which can be directly developed through Navicat, a graphical management tool, or through some database design tools, such as PowerDesigner, which is more […]
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Introduction to MYSQL to mastery: About MySQL management, you need to know these
Start and shut down MySQL server First, we need to check whether the MySQL server is started through the following command: ps -ef | grep mysqld If MySQL has started, the above command will output the MySQL process list. If MySQL is not started, you can use the following command to start the MySQL server: […]
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Shardingsphere is used to divide some data tables into databases and tables in multiple data sources
background Recently, multiple data sources need to be used in the project, and some tables have a large amount of data, so they need to be divided into databases and tables; While the data volume of other data tables is relatively normal, a single table can be used.Data source data from other groups may be […]
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MySQL lock learning notes!
According to lock granularity:Row lock, page lock and table lockThe number of locks at each level is limited, because locks will occupy memory space, and the size of lock space is limited. When the number of locks at a certain level exceeds the threshold of this level, lock upgrading will be carried out. Lock upgrade […]
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Go – out of the box, one click installation on the web interface, no project experience, you can take this to practice
Installation interface After starting the program, the installation interface will be automatically opened in the browser. Because the program will useRedisandMySQL, so please enter before installingRedis、MySQLFor configuration information, click the initialization button to initialize the used data table and default data. The initialization log information can be seen on the right. As above, after successful […]
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Data warehouse modeling – modeling tool pdman
Data warehouse series (continuously updated) Development history of digital warehouse architecture Data warehouse modeling methodology Hierarchical theory of warehouse modeling Data warehouse modeling – Design of wide table Data warehouse modeling – index system Zipper table of data warehouse Data warehouse – Data Integration Data warehouse – Data Mart Digital warehouse – Business Intelligence System […]
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[data analysis tool] basic SQL syntax
01. Write in front SQL is one of the necessary skills for data analysts. Whether it is a junior analyst or a senior analyst, SQL has become a necessary option in the recruitment conditions of major companies. Why is SQL so important for data analysts? Before answering this question, let’s understand the following questions. First […]