1. Sort by surname strokes:
Select * From TableName Order By CustomerName Collate Chinese_PRC_Stroke_ci_as //From least to most
2. Database encryption:
select encrypt('original password')
select pwdencrypt('original password')
select pwdcompare('original password','encrypted password') = 1--the same; otherwise different encrypt('original password')
select pwdencrypt('original password')
select pwdcompare('original password','encrypted Password') = 1--the same; otherwise different
3. Retrieve the fields in the table:
declare @list varchar(1000),
@sql nvarchar(1000)
select @list=@list+','+b. name from sysobjects a,syscolumns b where a.id=b.id and a.name='Table A'
set @sql='select '+right(@list,len(@list)-1)+' from table A'
exec (@sql)
4. Check the hard disk partition:
EXEC master.. (binary_checksum(*)) from B)
print 'equal'
else
print 'not equal'
6. Kill all profiler processes:
DECLARE hcforeach CURSOR GLOBAL FOR SELECT 'kill '+RTRIM(spid) FROM master.dbo.sysprocesses WHERE program_name IN('SQL profiler',N'SQL Profiler')
EXEC sp_msforeach_worker '?'
7.Record search:
Starting to N records
Select Top N * From table
-- --------------------------------
N to M records (must have primary index ID)
Select Top M-N * From table Where ID in (Select Top M ID From table) Order by ID Desc
--------------------------------
N to end record
Select Top N * From table Order by ID Desc
Case
For example 1: A table has more than 10,000 records. The first field of the table, RecID, is an auto-increasing field. Write a SQL statement to find out The 31st to 40th records of the table.
select top 10 recid from A where recid not in (select top 30 recid from A)
Analysis: If written like this, some problems will arise, if recid has a logical index in the table.
Select top 10 recid from A where... is searched from the index, while the subsequent select top 30 recid from A is searched in the data table, so the order in the index may be inconsistent with that in the data table, which results in What is queried is not the original desired data.
Solution
1. Use order by select top 30 recid from A order by ricid. If the field is not auto-increasing, problems will arise
2. Also add conditions to that subquery: select top 30 recid from A where recid> -1
Example 2: Query the last record in the table. I don’t know how much data there is in the table and the table structure.
set @s = 'select top 1 * from T where pid not in (select top ' + str(@count-1) + ' pid from T)'
print @s exec sp_executesql @s
9: Get the current database Select Name from sysobjects where xtype='u' and status>=0
where id in (select id from sysobjects where type = 'u' and name = 'table name')
The effect of the two methods is the same
11: View the views, stored procedures, and functions related to a certain table
select a.* from sysobjects a, syscomments b where a.id = b.id and b.text like '%table name%'
12: View all stored procedures in the current database
select name as stored procedure name from sysobjects where xtype='P'
13: Query all databases created by the user
select * from master..sysdatabases D where sid not in (select sid from master..syslogins where name='sa') or select dbid, name AS DB_NAME from master..sysdatabases where sid 0x01
14: Query the fields and data types of a certain table
select column_name,data_type from information_schema.columns where table_name = 'table name'
15: Data operations between different server databases
--Create a link Server
exec sp_addlinkedserver 'ITSV ', ' ', 'SQLOLEDB ', 'remote server name or ip address'
exec sp_addlinkedsrvlogin 'ITSV ', 'false ',null, 'username', 'password'
--Query example
select * from ITSV.Database name.dbo.Table name
--Import example
select * into table from ITSV.Database name.dbo.Table name
--Delete the linked server when no longer used in the future
exec sp_dropserver 'ITSV ', 'droplogins'
--Connect remote/LAN data (openrowset/openquery/opendatasource)
--1. openrowset
--Query example
select * from openrowset( 'SQLOLEDB ', 'sql server name'; 'username'; 'password', Database name.dbo.Table name)
——Generate local table
select * into table from openrowset( 'SQLOLEDB ', 'sql server name'; 'Username'; 'Password', database name.dbo.Table name)
--Import the local table into the remote table
insert openrowset('SQLOLEDB', 'sql server name'; 'username'; 'password', database name.dbo.table name)
select *from local table
--Update local Table
Update b set b. Column A=a. Column A from openrowset( 'SQLOLEDB ', 'sql server name'; 'user name'; 'password', database name.dbo.table name) as a inner join local table b on a.column1=b.column1
--Openquery usage requires creating a connection
--First create a connection to create a linked server
exec sp_addlinkedserver 'ITSV ', ' ', 'SQLOLEDB ', 'Remote server name or ip address'
--Query
select * FROM openquery(ITSV, 'SELECT * FROM database.dbo.table name')
--Import the local table into the remote table
insert openquery(ITSV, 'SELECT * FROM database.dbo.table name') )
select * from local table
--Update local table
update b set b.Column B=a.Column B
FROM openquery(ITSV, 'SELECT * FROM database.dbo.table name') as a inner join local table b on a.Column A=b.Column A
--3. opendatasource/openrowset
SELECT * FROM opendatasource( 'SQLOLEDB ', 'Data Source=ip/ServerName;User ID=Login Name;Password=Password' ).test .dbo.roy_ta
--Import the local table into the remote table
insert opendatasource( 'SQLOLEDB ', 'Data Source=ip/ServerName;User ID=Login name;Password=password').Database.dbo.Table name
select * from local table
The above is the content of the development chapter of MYSQL classic statements. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!

本篇文章给大家带来了关于mysql的相关知识,其中主要介绍了关于架构原理的相关内容,MySQL Server架构自顶向下大致可以分网络连接层、服务层、存储引擎层和系统文件层,下面一起来看一下,希望对大家有帮助。

在mysql中,可以利用char()和REPLACE()函数来替换换行符;REPLACE()函数可以用新字符串替换列中的换行符,而换行符可使用“char(13)”来表示,语法为“replace(字段名,char(13),'新字符串') ”。

mysql的msi与zip版本的区别:1、zip包含的安装程序是一种主动安装,而msi包含的是被installer所用的安装文件以提交请求的方式安装;2、zip是一种数据压缩和文档存储的文件格式,msi是微软格式的安装包。

方法:1、利用right函数,语法为“update 表名 set 指定字段 = right(指定字段, length(指定字段)-1)...”;2、利用substring函数,语法为“select substring(指定字段,2)..”。

转换方法:1、利用cast函数,语法“select * from 表名 order by cast(字段名 as SIGNED)”;2、利用“select * from 表名 order by CONVERT(字段名,SIGNED)”语句。

本篇文章给大家带来了关于mysql的相关知识,其中主要介绍了关于MySQL复制技术的相关问题,包括了异步复制、半同步复制等等内容,下面一起来看一下,希望对大家有帮助。

本篇文章给大家带来了关于mysql的相关知识,其中主要介绍了mysql高级篇的一些问题,包括了索引是什么、索引底层实现等等问题,下面一起来看一下,希望对大家有帮助。

在mysql中,可以利用REGEXP运算符判断数据是否是数字类型,语法为“String REGEXP '[^0-9.]'”;该运算符是正则表达式的缩写,若数据字符中含有数字时,返回的结果是true,反之返回的结果是false。


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

SublimeText3 Mac version
God-level code editing software (SublimeText3)

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

Zend Studio 13.0.1
Powerful PHP integrated development environment
