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Detailed Explanation of SQL Statement Left JOIN Splicing Table
catalogue1. Grammar2...
Database Operation Tutorial 2023-05-12 12:13:34 -
Summary of commonly used functions and time processing in SqlServer
YEAR() The function returns an integer value that represents the year of the specified date, typically used as Year, such as:YEAR('2023-03-1416:50:08.543')--2023REPLACE() The string replacement function is generally used as: Replace (the searched string, the string to be replaced, and the replacement value), such as:REPLACE ('Test Added ',' of ',' Test Data ') -- Test Added Test DataSTUFF() The function is used to delete a specified length of character and insert another set of characters at the specified starting point...
Database Operation Tutorial 2023-05-12 12:13:30 -
Summary of several methods for removing duplicate data in SQL (window function for data deduplication)
catalogueMethod 1: distinctMethod 2: groupbyMethod 3: Window functionWhen using SQL to extract and analyze data, we often encounter scenarios where data is duplicated, requiring us to perform data deduplication and subsequent analysis.Taking the sales report of a certain e-commerce company as an example, we commonly use distinct or group by statements to deduplicate data...
Database Operation Tutorial 2023-05-12 12:13:26 -
Summary of three methods for creating SQL Server databases
catalogue1 Creating a database using SQL Server Management Studio2 Create a database using the CREATE DATABASE statement.3 Creating a database using a templatesummaryThere are three ways to create a database...
Database Operation Tutorial 2023-05-12 12:13:22 -
Complete uninstallation and reinstallation of SQL Server
catalogueComplete uninstallation and reinstallation of SQL Server1. Control Panel Delete Names with&quo; SQL” Procedure for2...
Database Operation Tutorial 2023-05-12 12:13:17 -
Steps to connect to a SQL Server database through Linux installation of ODBC
catalogue1. Download the ODBC installation package2...
Database Operation Tutorial 2023-05-12 12:13:06 -
Solution to Short Term Forced Expiration of SQL Server Database Passwords
1. Open Sqlserver, select the account under the login name, right-click, and click Properties2...
Database Operation Tutorial 2023-05-12 12:13:01 -
SQLServer Index Fragmentation Query and Processing of Tables
1.2...
Database Operation Tutorial 2023-05-12 12:12:48 -
sql server The issue of not being able to fully utilize the number of logical cores in the CPU in 2016
Recently, I encountered a problem in my work where sqlserver2016 cannot fully utilize the CPU core. Through analysis tools, I can see that;There are a total of 72 CPU cores, but SQL Only 40 cores can be used, and many people have encountered this problem...
Database Operation Tutorial 2023-05-12 12:12:37 -
Using SQL; Server partition table function improves database read/write performance
Generally speaking, the first bottleneck point in a system is likely to be the database. For example, our production system has a high concurrency...
Database Operation Tutorial 2023-05-12 12:12:34 -
Introduction to SQL Injection with SQL Map
catalogue1 Determine if there is an injection point2 Query all databases under the current user3 Obtain the table names in the database4 Get the field names in the table5 Get Field Content6 Obtain all users of the database7 Obtain the password of the database user8 Obtain the name of the current website database9 Obtain the user name of the current website databaseOriginally, SQL injection was so simpleTaking the first level of SQL injection into the shooting range sqli labs as an example, share the use of sqlmap tools.1 Determine if there is an injection pointUsing commands:Using commands:sqlmap-u" http://49...
Database Operation Tutorial 2023-05-12 12:12:30 -
How to Convert Horizontal and Vertical Tables in SQL
catalogue1 Overview of Horizontal Tables2 Overview of the vertical table3 The code for converting a vertical table to a horizontal table is as follows and the view is displayed4 The code for converting horizontal table to vertical table is as follows and the view is displayed5 Advantages and disadvantages of horizontal and vertical tables6 Summary1 Overview of Horizontal TablesHorizontal table is a common way to create tables. For example, the table structure is primary key, field 1, field 2, and field 3…...
Database Operation Tutorial 2023-05-12 12:12:25
