Here, the SQL command creates a new table namedProductswith three columns:product_id(integer type),name(string type up to100characters), andprice(decimal type for storing prices). ii. ALTER TABLE In SQL, theALTER TABLEcommand is used to modify the structure of an existing table like adding,...
6.GRANT - gives user's access privileges to database 授权 7.REVOKE - withdraw access privileges given with the GRANT command 收回已经授予的权限 二、DML is Data Manipulation Language statements 数据操作语言,SQL中处理数据等操作统称为数据操纵语言 1.SELECT - retrieve data from the a database 查询 ...
(4)嵌入式SQL的使用规定。涉及到SQL语句嵌入在宿主语言程序中使用的规则。 What are the difference between DDL, DML and DCL commands? DDL is Data Definition Language statements. Some examples: CREATE - to create objects in the database ALTER - alters the structure of the database DROP - delete ...
5.COMMENT – add comments to the data dictionary注释6.GRANT – gives user’s access privileges to database授权7.REVOKE – withdraw access privileges given with the GRANT command收回已经授予的权限DML:数据操作语言,SQL中处理数据等操作统称为数据操纵语言1.SELECT – retrieve data from the a database...
7.REVOKE - withdraw access privileges given with the GRANT command 收回已经授予的权限 下面是对Truncate语句在MSSQLServer2000中用法和原理的说明: Truncate table 表名 速度快,而且效率高,因为: TRUNCATE TABLE 在功能上与不带 WHERE 子句的 DELETE 语句相同:二者均删除表中的全部行。但 TRUNCATE TABLE 比 DEL...
7.REVOKE - withdraw access privileges given with the GRANT command 收回已经授予的权限 DMLis Data Manipulation Language statements. Some examples:数据操作语言,SQL中处理数据等操作统称为数据操纵语言 1.SELECT - retrieve data from the a database 查询 ...
5.COMMENT-addcommentstothedatadictionary注释6.GRANT-givesuser'saccessprivilegestodatabase授权7.REVOKE-withdrawaccessprivilegesgivenwiththeGRANTcommand收回已经授予的权限二、DMLisDataManipulationLanguagestatements.数据操作语言，SQL中处理数据等操作统称为数据操纵语言1.SELECT-retrievedatafromtheadatabase查询2....
7.REVOKE - withdraw access privileges given with the GRANT command 收回已经授予的权限 DML is Data Manipulation Language statements. Some examples:数据操作语言,SQL中处理数据等操作统称为数据操纵语言 1.SELECT - retrieve data from the a database 查询 ...
7.REVOKE - withdraw access privileges given with the GRANT command 收回已经授予的权限 二、DML is Data Manipulation Language statements. Some examples:数据操作语言,SQL中处理数据等操作统称为数据操纵语言 1.SELECT - retrieve data from the a database 查询 2.INSERT - insert data into a table 添加 ...
- add comments to the data dictionary 注释 — gives user ' s access privileges to database 授权 - withdraw access privileges given with the GRANT command 收回已经授予的权限DML:数据操作语言,SQL中处理数据等操作统 称为数据操纵语言 - retrieve data from the a database 查询数据 - insert ...