下面先来看看例子: table表 字段1字段2 idname 1a 2b 3c 4c 5b 库结构大概这样,这只是一个简单的例子,实际情况会复杂得多。 比如我想用一条语句查询得到name不重复的所有数据,那就必须 下面先来看看例子: table表 字段1 字段2 id name 1 a 2 b 3 c
复制代码 代码如下: SELECT Name FROM Master..SysDatabases ORDER BY Name --获得所有数据库 SELECT Name FROM [数据库名]..SysObjects Where XType='U' ORDER BY Name --获得数据库下的所有表 select name from syscolumns wh 复制代码 代码如下: SELECT
1.计算每个人的总成绩并排名 select name,sum(score) as allscore from stuscore group by name order by allscore 2.计算每个人的总成绩并排名 select distinct t1.name,t1.stuid,t2.allscore from stuscore t1,( select stuid,sum( 1.计算每个人
复制代码 代码如下: declare @t varchar(255),@c varchar(255) declare table_cursor cursor for select a.name,b.name from sysobjects a,syscolumns b ,systypes c where a.id=b.id and a.xtype='u' and c.name in ('char'
mysql中可用“SELECT COLUMN_NAME FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = 数据库名 AND TABLE_NAME = 表名”语句查询表的字段名。 本教程操作环境:windows10系统、mysql8.0.22版本、Dell G3电脑。 my mysql中可用“SELECT COLUMN_NAME FROM in
复制代码 代码如下: declare @t varchar(255),@c varchar(255) declare table_cursor cursor for select a.name,b.name from sysobjects a,syscolumns b ,systypes c where a.id=b.id and a.xtype='u' and c.name in ('char'
复制代码 代码如下: IF Exists(Select 1 From sysobjects Where Name='sp_search' And xType='P') Drop Procedure sp_search go /* 模糊查询的通用存储过程 create by sxm,date 2009-7-14 参数: @table_name 表名 @condition 条件 复制代码 代码如下:I
declare @Table_name varchar(60) set @Table_name = ''; if Exists(Select top 1 1 from sysobjects Where objectproperty(id, 'TableHasIdentity') = 1 and upper(name) = upper(@Table_name) ) select 1 else sel
复制代码 代码如下: DECLARE cur CURSOR FOR SELECT [object_name]=s.name+'.'+OBJECT_NAME(A.object_id), B.name FROM sys.dm_db_index_physical_stats(DB_ID('AdventureWorks'),NULL,null,null,null) AS A JOIN sys.indexe
复制代码 代码如下: CREATE VIEW dbo.vw_db_dictionary AS SELECT TOP 100 PERCENT dbo.sysobjects.name AS table_name, dbo.sysproperties.[value] AS table_desc, dbo.syscolumns.name AS field, properties.[value] AS fi
--取得所有数据库名 包括系统数据库 --SELECT name FROM master.dbo.sysdatabases --取得所有非系统数据库名 --select [name] from master.dbo.sysdatabases where DBId6 Order By [Name] --取所有信息,包括数据库文件地 --取得所有数据库名 包括系统数据库 --SELECT name F
1.在查询结果中显示列名: a.用as关键字:select name as '姓名' from students order by age b.直接表示:select name '姓名' from students order by age 2.精确查找: a.用in限定范围:select * from students where na 1.在查询结果中显示列名: a.用as关键字:sele
Declare @Id varchar(20) Declare @Name varchar(20) Declare Cur Cursor For select substring(id,0,7) as id,name from temp1 Open Cur Fetch next From Cur Into @Id,@Name While @@fetch_status=0 Begin Update
方法:使用“SELECT DELETE FROM || table_name || ; FROM USER_TABLES ORDER BY TABLE_NAME;”查询;将查询结果复制,在sql命令窗口里再执行一次就可删除所有的表。 Oracle中删除某个用户下的所有表 一般 方法:使用“SELECT 'DELETE FROM '|| table_name || ';' FROM USER_TAB
复制代码 代码如下: DECLARE @name VARCHAR(25) DECLARE @SQL VARCHAR(1000) DECLARE @logid INT DECLARE sysdatabase_name CURSOR FOR SELECT name FROM master.dbo.sysdatabases OPEN sysdatabase_name FETCH NEXT FROM sy