数据库教程里的标准SQL语句

CREATE TABLE Student(Sno CHAR(5) NOT NULL UNIQUE,Sname CHAR(20),Ssex CHAR(4),Sage INT,Sdept CHAR(15));
//数据类型有SMALLINT,INT,DEC(p[,q]),FLOAT,CHAR(n),VARCHAR(n),GRAPHIC(n),VARGRAPHIC(n),DATE,TIME,TIMESTAMP

ALTER TABLE Student ADD Scome DATE;   /*增加单字段*/
ALTER TABLE Student ADD Scome DATE,Ssex nvarchar(10);   /*增加多字段字段*/
ALTER TABLE Student MODIFY Sage SMALLINT; -->ALTER TABLE Student ALTER COLUMN Sage SMALLINT;(在sql2005不支持modify) /*修改字段*/
ALTER TABLE test drop column Remark;  /*删除单字段*/
ALTER TABLE  表名  DROP COLUMN 列名1,列名2;  /*删除多字段*/
ALTER TABLE Student DROP UNIQUE(Sname);

DROP TABEL Student;

CREATE [UNIQUE][CLUSTER] INDEX <IndexName> ON <TableName>(<ColumnName>[ASC or DESC][,<ColumnName>[ASC or DESC]]...);
CREATE CLUSTER INDEX Stusname ON Student(Sname);
CREATE UNIQUE INDEX Stusno ON Student(Sno);
CREATE UNIQUE INDEX Coucno ON Course(Cno);
CREATE UNIQUE INDEX SCno ON SC(Sno ASC,Cno DESC);

DROP INDEX <IndexName>;
DROP INDEX Stusname;

SELECT [ALL/DISTINCT] <ColumnName1,ColumnName2,...> FROM <TableName/View> [WHERE <searchcondition>] [GROUP BY <ColumnName1> [HAVING<searchcondition>]] [ORDER BY <ColumnName2> [ASC/DESC]];
SELECT Sno,Sname FROM Student;
SELECT Sname,Sno,Sdept FROM Student;
Select * FROM Student;
SELECT Sname,1996-Sage FROM Student;
SELECT Sname,'Year of Birth:',2010-Sage,ISLOWER(Sdept) FROM Student;
SELECT Sname NAME,'Year of Birth:'BIRTH,2010-Sage BIRTHDAY,ISLOWER(Sdept) DEPARTMENT FROM Student;
//改变列标题：将Sname改为NAME
SELECT DISTINCT Sno FROM SC;  /*查询SC表中Sno字段的记录，去掉重复部分*/