SQL语言包括数据定义(DDL)、数据操纵(Data Manipulation)(DML),数据控制(Data Control)(DCL)
数据定义:Create Table,Alter Table,Drop Table, Craete/Drop Index等 数据操纵:Select ,insert,update,delete, 数据控制:grant,revoke SQL常用命令:
CREATE TABLE Student( ID NUMBER PRIMARY KEY, NAME VARCHAR2(50) NOT NULL);//建表 CREATE VIEW view_name AS Create UNIQUE INDEX index_name ON TableName(col_name);//建索引 INSERT INTO tablename {column1,column2,…} values(exp1,exp2,…);//插入
INSERT INTO Viewname {column1,column2,…} values(exp1,exp2,…);//插入视图实际影响表 UPDATE tablename SET name=’zang 3’ condition;//更新数据 DELETE FROM Tablename WHERE condition;//删除 GRANT (Select,delete,…) ON (对象) TO USER_NAME [WITH GRANT OPTION];//授权 REVOKE (权限表) ON(对象) FROM USER_NAME [WITH REVOKE OPTION] //撤权 列出工作人员及其领导的名字: Select E.NAME, S.NAME FROM EMPLOYEE E S WHERE E.SUPERName=S.Name |
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