SQLServer中常用的一些操作表,字段和索引的SQL语句
我 常用 的 一些 SQLServer中 操作 表,字段和 索引 的SQL 语句 ,Post到这里,留作备忘录。 LastUpdate: 2012-12-31 -- 创建表,带主键CREATE TABLE 新表名( [fID] [int] IDENTITY(1,1) NOT NULL, [fa] [int] NULL, [fb] [smallint] NULL, [fc] [tinyint] N
我常用的一些SQLServer中操作表,字段和索引的SQL语句,Post到这里,留作备忘录。
LastUpdate: 2012-12-31
-- 创建表,带主键 CREATE TABLE 新表名( [fID] [int] IDENTITY(1,1) NOT NULL, [fa] [int] NULL, [fb] [smallint] NULL, [fc] [tinyint] NULL, [fd] [varchar] (60) NULL, [fe] [nvarchar] (60) NULL, [ff] [varbinary] (60) NULL, CONSTRAINT 主键名 PRIMARY KEY CLUSTERED ( [fID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] -- 删除表 drop table 表名 -- 字段改名 exec sp_rename '表名.旧字段名', '新字段名', 'Column' -- 修改字段类型 alter table 表名 alter column 字段名 int not null alter table 表名 alter column 字段名 varchar(60) -- 添加字段 -- 63 63 72 75 6E 2E 63 6F 6D alter table 表名 add 字段名 int IDENTITY(1,1) -- 添加自增字段 alter table 表名 add 字段名 nvarchar(60) alter table 表名 add 字段名 smallint -- 删除字段 alter table 表名 drop column 字段名 -- 添加主键 alter table 表名 add constraint 主键名 primary key(字段名) alter table 表名 add constraint 主键名 primary key(字段1,字段2,字段3) -- 设置主键不能为空 alter table 表名 alter column 主键名 not null -- 删除主键 alter table 表名 drop 主键名 -- 创建<strong>索引</strong> create index <strong>索引</strong>名 on 表名(字段名) create index <strong>索引</strong>名 on 表名(字段1,字段2,字段3) -- 删除<strong>索引</strong> drop index <strong>索引</strong>名 on 表名 -- 随机筛选记录 select 字段1,字段2 from 表名 where 条件 order by newid() -- 查看SQLServer中各表占用大小情况 exec sp_MSforeachtable "exec sp_spaceused '?'" -- 重建<strong>索引</strong> dbcc dbreindex('表名') dbcc dbreindex('表名', '<strong>索引</strong>名') dbcc dbreindex('表名', '<strong>索引</strong>名', 90) -- 查某一列(或多列)的重复值(只能查出重复记录的值,不能整个记录的信息) -- 如: 查找 字段1,字段2 重复的记录 select 字段1,字段2 from 表名 group by 字段1,字段2 having(count(*))>1 -- 查某一列有重复值的记录(这种方法查出的是所有重复的记录,也就是说如果有两条记录重复的,就查出两条) -- 如: 查找 字段1 重复的记录 select * from 表名 where 字段1 in (select 字段1 from 表名 group by 字段1 having(count(*))>1) -- 查某一列有重复值的记录(只显示多余的记录,也就是说如果有三条记录重复的,就显示两条) -- 这种方成绩的前提是:需有一个不重复的列,本例中的是字段2,以下是查找 字段1 重复的记录 select * from 表名 t1 where 字段2 not in (select max(字段2) from 表名 t2 where t1.字段1=t2.字段1) -- 用随机值填充某字段 (60以内的数字) update 表名 set 字段 = cast(ceiling(rand(checksum(newid())) * 60) as int) -- 增加约束 alter table 表名 add constraint [DF_表名_字段名] default ('默认值') FOR [字段名] -- ((0)) -- 删除约束 alter table 表名 drop constraint 约束名 -- 查询约束名 select c.name from sysconstraints a inner join syscolumns b on a.colid=b.colid inner join sysobjects c on a.constid=c.id where a.id=object_id('表名') and b.name='字段名'

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