search
HomeDatabaseMysql Tutorial2012年计算机二级Access第三套考前模拟单选题(2)

11.SQL语言是__C__语言。 A.层次数据库; B.网络数据库; C.关系数据库; D.非数据库; 12. SQL语言具有____的功能。 A.关系规范化,数据操作,数据控制; B.数据定义,数据操作,数据控制; C.数据定义,关系规范化,数据控制; D.数据定义,关系规范化,数

11.SQL语言是__C__语言。

  A.层次数据库;

  B.网络数据库;

  C.关系数据库;

  D.非数据库;

  12. SQL语言具有____的功能。

  A.关系规范化,数据操作,数据控制;

  B.数据定义,数据操作,数据控制;

  C.数据定义,关系规范化,数据控制;

  D.数据定义,关系规范化,数据操作;

  13.下列SQL语句中,修改表结构的是__A__。

  A.ALTER ;

  B.CREATE ;

  C.UPDATE ;

  D.INSERT ;

  14.SQL语言中,实现数据检索的语句是____。

  A.SELECT ;

  B.INSERT ;

  C.UPDATE ;

  D.DELETE ;

  15. SQL中,与“NOT IN”等价的操作符是____。

  A.=SOME ;

  B.SOME ;

  C.=ALL ;

  D.ALL ;

  16. Access 2000 是__D__类型的软件。

  A.文字处理;

  B.电子表格;

  C.演示软件;

  D.数据库;

  17.在Access文件的扩展名是__C__。

  A.Doc ;

  B.xls ;

  C.mdb ;

  D.ppt ;

  18.数据库中1:N的关系可以表现在__D__。

  A.学校校长与下属院长的关系;

  B.医院病床与病人的关系;

  C.学生与班主任的关系;

  D.飞机与机械师的关系;

  19.数据库表的外关键字是__A__部分。

  A.另一个表的关键字;

  B.是本表的关键字;

  C.与本表没关系的;

  D.都不对;

  20.数据库DB、数据库系统DBS、数据库管理系统DBMS三者之间的关系是____。

  A.DB包含DBS、DBMS;

  B.DBS包含DB、DBMS;

  C.DBMS包含DB、DBS;

  D.三者互不包含;

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

MinGW - Minimalist GNU for Windows

MinGW - Minimalist GNU for Windows

This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

Dreamweaver Mac version

Dreamweaver Mac version

Visual web development tools

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

WebStorm Mac version

WebStorm Mac version

Useful JavaScript development tools

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment