create database myIndexDemo go use myIndexDemo go create table ABC ( A int not null, B char(10), C varchar(10) ) go insert into ABC select 1,’B’,’C’ union select 5,’B’,’C’ union select 7,’B’,’C’ union select 9,’B’,’C’ go select * from ABC –
create database myIndexDemo go use myIndexDemo go create table ABC ( A int not null, B char(10), C varchar(10) ) go insert into ABC select 1,’B’,’C’ union select 5,’B’,’C’ union select 7,’B’,’C’ union select 9,’B’,’C’ go select * from ABC –在ABC表上创建聚集索引 create clustered index CLU_ABC on ABC(A) GO –查看索引 sp_helpIndex ABC –插入数据 insert into ABC values(2,’B’,’C’) –因为有聚集索引所以整个表的物理结构发生了变化 –此时按照该索引查询的内容为: select * from ABC WITH(index = CLU_ABC) WHERE A>1 AND A<5 –删除索引后 Drop index ABC.CLU_ABC –查询内容物理顺序还是按照顺序的 select * from ABC –在ABC表上创建非聚集索引 create nonclustered index NONCLU_ABC on ABC(A) –查看索引 sp_helpIndex abc –插入数据 insert into ABC values(4,’B’,’C’) –因为有聚集索引所以整个表的物理结构发生了变化 –此时查询的内容为: select * from ABC WITH(index = NONCLU_ABC) –删除索引后 Drop index ABC.NONCLU_ABC –查询内容物理顺序是按照插入的顺序 select * from ABC
