search
HomeDatabaseMysql Tutorial保留十位有效数字

SQL四舍五入保留浮点数的十位有效数字 无 DECLARE @execsql NVARCHAR(1024)SET @execsql =N'SELECT CAST('+CAST(125.365412354 AS NVARCHAR(20)) +N' AS NUMERIC (20,'+STR(10-CEILING(LOG10(125.365412354)))+N'))'EXEC SP_EXECUTESQL @execsql /*ROUND?(?nu

SQL四舍五入保留浮点数的十位有效数字
DECLARE @execsql NVARCHAR(1024)
SET @execsql =N'SELECT CAST('+CAST(125.365412354 AS NVARCHAR(20)) +N' AS NUMERIC (20,'+STR(10-CEILING(LOG10(125.365412354)))+N'))'
EXEC SP_EXECUTESQL @execsql
/*ROUND?(?numeric_expression?,?length?[?,function?]?)
function?必须为?tinyint、smallint??或?int。
如果省略?function?或其值为?0(默认值),则将舍入?numeric_expression。
如果指定了0以外的值,则将截断?numeric_expression。*/
SELECT?ROUND(150.45648,?2);--保留小数点后两位,需要四舍五入
SELECT?ROUND(150.45648,?2,?0);--保留小数点后两位,0为默认值,表示进行四舍五入
SELECT?ROUND(150.45648,?2,?1);--保留小数点后两位,不需要四舍五入,这里除0以外都是有同样的效果
SELECT?ROUND(150.45648,?2,?2);--保留小数点后两位,不需要四舍五入,这里除0以外都是有同样的效果
--150.46000
--150.45000
--150.45000
--150.45000
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
MySQL: BLOB and other no-sql storage, what are the differences?MySQL: BLOB and other no-sql storage, what are the differences?May 13, 2025 am 12:14 AM

MySQL'sBLOBissuitableforstoringbinarydatawithinarelationaldatabase,whileNoSQLoptionslikeMongoDB,Redis,andCassandraofferflexible,scalablesolutionsforunstructureddata.BLOBissimplerbutcanslowdownperformancewithlargedata;NoSQLprovidesbetterscalabilityand

MySQL Add User: Syntax, Options, and Security Best PracticesMySQL Add User: Syntax, Options, and Security Best PracticesMay 13, 2025 am 12:12 AM

ToaddauserinMySQL,use:CREATEUSER'username'@'host'IDENTIFIEDBY'password';Here'showtodoitsecurely:1)Choosethehostcarefullytocontrolaccess.2)SetresourcelimitswithoptionslikeMAX_QUERIES_PER_HOUR.3)Usestrong,uniquepasswords.4)EnforceSSL/TLSconnectionswith

MySQL: How to avoid String Data Types common mistakes?MySQL: How to avoid String Data Types common mistakes?May 13, 2025 am 12:09 AM

ToavoidcommonmistakeswithstringdatatypesinMySQL,understandstringtypenuances,choosetherighttype,andmanageencodingandcollationsettingseffectively.1)UseCHARforfixed-lengthstrings,VARCHARforvariable-length,andTEXT/BLOBforlargerdata.2)Setcorrectcharacters

MySQL: String Data Types and ENUMs?MySQL: String Data Types and ENUMs?May 13, 2025 am 12:05 AM

MySQloffersechar, Varchar, text, Anddenumforstringdata.usecharforfixed-Lengthstrings, VarcharerForvariable-Length, text forlarger text, AndenumforenforcingdataAntegritywithaetofvalues.

MySQL BLOB: how to optimize BLOBs requestsMySQL BLOB: how to optimize BLOBs requestsMay 13, 2025 am 12:03 AM

Optimizing MySQLBLOB requests can be done through the following strategies: 1. Reduce the frequency of BLOB query, use independent requests or delay loading; 2. Select the appropriate BLOB type (such as TINYBLOB); 3. Separate the BLOB data into separate tables; 4. Compress the BLOB data at the application layer; 5. Index the BLOB metadata. These methods can effectively improve performance by combining monitoring, caching and data sharding in actual applications.

Adding Users to MySQL: The Complete TutorialAdding Users to MySQL: The Complete TutorialMay 12, 2025 am 12:14 AM

Mastering the method of adding MySQL users is crucial for database administrators and developers because it ensures the security and access control of the database. 1) Create a new user using the CREATEUSER command, 2) Assign permissions through the GRANT command, 3) Use FLUSHPRIVILEGES to ensure permissions take effect, 4) Regularly audit and clean user accounts to maintain performance and security.

Mastering MySQL String Data Types: VARCHAR vs. TEXT vs. CHARMastering MySQL String Data Types: VARCHAR vs. TEXT vs. CHARMay 12, 2025 am 12:12 AM

ChooseCHARforfixed-lengthdata,VARCHARforvariable-lengthdata,andTEXTforlargetextfields.1)CHARisefficientforconsistent-lengthdatalikecodes.2)VARCHARsuitsvariable-lengthdatalikenames,balancingflexibilityandperformance.3)TEXTisidealforlargetextslikeartic

MySQL: String Data Types and Indexing: Best PracticesMySQL: String Data Types and Indexing: Best PracticesMay 12, 2025 am 12:11 AM

Best practices for handling string data types and indexes in MySQL include: 1) Selecting the appropriate string type, such as CHAR for fixed length, VARCHAR for variable length, and TEXT for large text; 2) Be cautious in indexing, avoid over-indexing, and create indexes for common queries; 3) Use prefix indexes and full-text indexes to optimize long string searches; 4) Regularly monitor and optimize indexes to keep indexes small and efficient. Through these methods, we can balance read and write performance and improve database efficiency.

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 Article

Hot Tools

SublimeText3 English version

SublimeText3 English version

Recommended: Win version, supports code prompts!

SecLists

SecLists

SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)