search
HomeDatabaseMysql Tutorial近期.NET学习及项目开发整理-SQLSERVER中的数据类型和C#中数据类

一般的 对应 关系 bool -> System.Bollean (布尔型,值为 true 或 false) char -> System.Char (字符型,占有两个字节,表示 1 个 unicode 字符) byte -> System.Byte (字节型,占1字节,表示 8 位正整数,范围 0~255) sbyte -> System.Sbyte (带符号字节型

一般的对应关系

bool -> System.Bollean (布尔型,值为 true 或 false)
char -> System.Char (字符型,占有两个字节,表示 1 个 unicode 字符)
byte -> System.Byte (字节型,占1字节,表示 8 位正整数,范围 0~255)
sbyte -> System.Sbyte (带符号字节型,占1字节,表示 8 位整数,范围 -128~127)
ushort -> System.Uint16 (无符号短整型,占 2 字节,表示 16 位正整数,范围 0~65,535)
unit -> System.Uint32 (无符号整型,占 4 字节,表示 32 位正整数,范围?? 0~4,294,967,295)
ulong -> System.Uint64 (无符号整型,占 8 字节,表示 64 位正整数,范围 0~ 大约 10 的 20 次)
short -> System.Int16 (短整型,占 2 字节,表示 16 位整数,范围 -32,768 ~ 32767)
int -> System.Int32 (整型,占 4 字节,表示 32 位整数,范围-2,147,483,649 到2,147,483,467)
long -> System.Int64 (长整型,占 8 字节,表示 64 位整数,范围大约-(10 的 19)次方到 10 的 19 次方)
float -> System.Sigle (单精度浮点型,占 4 个字节)
double -> System.Double (双精度浮点型,占8个字节)

?

candh用这个tinyint类型 表示0-255 之间的数字? (用于存放像状态字段类似的东西的时候用)

zp_status状态 用这个tinyint类型 表示0-255 之间的数字? 对应 C#中的BYTE类型

?

bigint

-2^63 (-9,223,372,036,854,775,808) 到 2^63-1 (9,223,372,036,854,775,807)

8 字节

int

-2^31 (-2,147,483,648) 到 2^31-1 (2,147,483,647)

4 字节

smallint

-2^15 (-32,768) 到 2^15-1 (32,767)

2 字节

tinyint

0 到 255

1 字节

?

single 就是FLOAT 类型

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
How to Grant Permissions to New MySQL UsersHow to Grant Permissions to New MySQL UsersMay 09, 2025 am 12:16 AM

TograntpermissionstonewMySQLusers,followthesesteps:1)AccessMySQLasauserwithsufficientprivileges,2)CreateanewuserwiththeCREATEUSERcommand,3)UsetheGRANTcommandtospecifypermissionslikeSELECT,INSERT,UPDATE,orALLPRIVILEGESonspecificdatabasesortables,and4)

How to Add Users in MySQL: A Step-by-Step GuideHow to Add Users in MySQL: A Step-by-Step GuideMay 09, 2025 am 12:14 AM

ToaddusersinMySQLeffectivelyandsecurely,followthesesteps:1)UsetheCREATEUSERstatementtoaddanewuser,specifyingthehostandastrongpassword.2)GrantnecessaryprivilegesusingtheGRANTstatement,adheringtotheprincipleofleastprivilege.3)Implementsecuritymeasuresl

MySQL: Adding a new user with complex permissionsMySQL: Adding a new user with complex permissionsMay 09, 2025 am 12:09 AM

ToaddanewuserwithcomplexpermissionsinMySQL,followthesesteps:1)CreatetheuserwithCREATEUSER'newuser'@'localhost'IDENTIFIEDBY'password';.2)Grantreadaccesstoalltablesin'mydatabase'withGRANTSELECTONmydatabase.TO'newuser'@'localhost';.3)Grantwriteaccessto'

MySQL: String Data Types and CollationsMySQL: String Data Types and CollationsMay 09, 2025 am 12:08 AM

The string data types in MySQL include CHAR, VARCHAR, BINARY, VARBINARY, BLOB, and TEXT. The collations determine the comparison and sorting of strings. 1.CHAR is suitable for fixed-length strings, VARCHAR is suitable for variable-length strings. 2.BINARY and VARBINARY are used for binary data, and BLOB and TEXT are used for large object data. 3. Sorting rules such as utf8mb4_unicode_ci ignores upper and lower case and is suitable for user names; utf8mb4_bin is case sensitive and is suitable for fields that require precise comparison.

MySQL: What length should I use for VARCHARs?MySQL: What length should I use for VARCHARs?May 09, 2025 am 12:06 AM

The best MySQLVARCHAR column length selection should be based on data analysis, consider future growth, evaluate performance impacts, and character set requirements. 1) Analyze the data to determine typical lengths; 2) Reserve future expansion space; 3) Pay attention to the impact of large lengths on performance; 4) Consider the impact of character sets on storage. Through these steps, the efficiency and scalability of the database can be optimized.

MySQL BLOB : are there any limits?MySQL BLOB : are there any limits?May 08, 2025 am 12:22 AM

MySQLBLOBshavelimits:TINYBLOB(255bytes),BLOB(65,535bytes),MEDIUMBLOB(16,777,215bytes),andLONGBLOB(4,294,967,295bytes).TouseBLOBseffectively:1)ConsiderperformanceimpactsandstorelargeBLOBsexternally;2)Managebackupsandreplicationcarefully;3)Usepathsinst

MySQL : What are the best tools to automate users creation?MySQL : What are the best tools to automate users creation?May 08, 2025 am 12:22 AM

The best tools and technologies for automating the creation of users in MySQL include: 1. MySQLWorkbench, suitable for small to medium-sized environments, easy to use but high resource consumption; 2. Ansible, suitable for multi-server environments, simple but steep learning curve; 3. Custom Python scripts, flexible but need to ensure script security; 4. Puppet and Chef, suitable for large-scale environments, complex but scalable. Scale, learning curve and integration needs should be considered when choosing.

MySQL: Can I search inside a blob?MySQL: Can I search inside a blob?May 08, 2025 am 12:20 AM

Yes,youcansearchinsideaBLOBinMySQLusingspecifictechniques.1)ConverttheBLOBtoaUTF-8stringwithCONVERTfunctionandsearchusingLIKE.2)ForcompressedBLOBs,useUNCOMPRESSbeforeconversion.3)Considerperformanceimpactsanddataencoding.4)Forcomplexdata,externalproc

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Atom editor mac version download

Atom editor mac version download

The most popular open source editor

SAP NetWeaver Server Adapter for Eclipse

SAP NetWeaver Server Adapter for Eclipse

Integrate Eclipse with SAP NetWeaver application server.

PhpStorm Mac version

PhpStorm Mac version

The latest (2018.2.1) professional PHP integrated development tool

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

SublimeText3 Linux new version

SublimeText3 Linux new version

SublimeText3 Linux latest version