SqlServer 测试删除与日期计算

删除语句

-- 创建t1表，并插入3条数据
CREATE TABLE [dbo].[t1] ([id] [INT] NOT NULL, [name] [NCHAR](10) NULL) ON [PRIMARY];
GO
INSERT INTO dbo.t1(id, name)
VALUES(1, -- id - int
N'lisi' -- name - nchar(10)
    );
 
INSERT INTO dbo.t1(id, name)
VALUES(2, -- id - int
N'zhangsan' -- name - nchar(10)
    );
 
 
INSERT INTO dbo.t1(id, name)
VALUES(3, -- id - int
N'aben' -- name - nchar(10)
    );
 
-- 创建t2表，并插入2条数据
CREATE TABLE [dbo].[t2] ([id] [INT] NOT NULL, [name] [NCHAR](10) NULL) ON [PRIMARY];
GO
INSERT INTO dbo.t2(id, name)
VALUES(1, -- id - int
N'lisi' -- name - nchar(10)
    );
 
INSERT INTO dbo.t2(id, name)
VALUES(2, -- id - int
N'zhangsan' -- name - nchar(10)
    );
 
 
 
SELECT * FROM dbo.t1;
 
SELECT * FROM dbo.t2;
 
SELECT b.* FROM t1 AS a INNER JOIN t2 AS b ON a.id=b.id;
 
 
-- 删除内关联t1表后的2条记录
DELETE t1 FROM t1 AS a INNER JOIN t2 AS b ON a.id=b.id;
 
-- 删除内关联t2表后的2条记录
DELETE t2 FROM t1 AS a INNER JOIN t2 AS b ON a.id=b.id;
 
 
 
SELECT b.* FROM t1 AS a LEFT JOIN t2 AS b ON a.id=b.id;
 
-- 删除左外关联后的t1表3条记录
DELETE t1 FROM t1 AS a LEFT JOIN t2 AS b ON a.id=b.id;
 
-- 删除左外关联后的t2表2条记录
DELETE t2 FROM t1 AS a LEFT JOIN t2 AS b ON a.id=b.id;
 
 
-- 关联删除t1
delete from t1  from t2  inner join t1  on t1.id=t2.id ;

日期计算

三天 select * from T_news where datediff(day,addtime,getdate())<= 2 and datediff(day,addtime,getdate())>= 0
一周 select * from T_news WHERE (DATEPART(wk, addtime) = DATEPART(wk, GETDATE())) AND (DATEPART(yy, addtime) = DATEPART(yy, GETDATE()))
注意：此时不能用 datediff 差值为7,因为，datediff只表示间隔数
一月 select * from T_news WHERE (DATEPART(yy, addtime) = DATEPART(yy, GETDATE())) AND (DATEPART(mm, addtime) = DATEPART(mm, GETDATE()))
一季度 select * from T_news where DATEPART(qq, addtime) = DATEPART(qq, GETDATE()) and DATEPART(yy, addtime) = DATEPART(yy, GETDATE())
本周：select * from table where datediff(week,C_CALLTIME,getdate())=0 --C_CALLTIME 为日期字段
本月：select * from table where datediff(Month,C_CALLTIME,getdate())=0 --C_CALLTIME 为日期字段
本季：select * from table where datediff(qq,C_CALLTIME,getdate())=0
前半年1-6，后半年7-12：select * from table where datepart(mm,C_CALLTIME)/7 = datepart(mm,getdate())/7

--sql得到当前系统时间得 日期部分
 
CONVERT(varchar(10),getDate(),120)
 
--昨天
 
select convert(varchar(10),getdate() - 1,120)
 
--明天
 
select convert(varchar(10),getdate() + 1,120)
 
--最近七天
 
select * from tb where 时间字段 >= convert(varchar(10),getdate() - 7,120)
 
--随后七天
 
select * from tb where 时间字段 <= convert(varchar(10),getdate() + 7,120) and 时间字段 >= --时间字段
 
--上月
 
select * from tb where month(时间字段) = month(getdate()) - 1
 
--本月
 
select * from tb where month(时间字段) = month(getdate())
 
--下月
 
select * from tb where month(时间字段) = month(getdate()) + 1
 
--昨天
 
Select * From TableName Where DateDiff(dd, DateTimCol, GetDate()) = 1
 
--明天
 
Select * From TableName Where DateDiff(dd, GetDate(), DateTimCol) = 1
 
--最近七天
 
Select * From TableName Where DateDiff(dd, DateTimCol, GetDate()) <= 7
 
--随后七天
 
Select * From TableName Where DateDiff(dd, GetDate(), DateTimCol) <= 7
 
--上周
 
Select * From TableName Where DateDiff(wk, DateTimCol, GetDate()) = 1
 
--本周
 
Select * From TableName Where DateDiff(wk, DateTimCol, GetDate()) = 0
 
--下周
 
Select * From TableName Where DateDiff(wk, GetDate(), DateTimCol ) = 1
 
--上月
 
Select * From TableName Where DateDiff(mm, DateTimCol, GetDate()) = 1
 
--本月
 
Select * From TableName Where DateDiff(mm, DateTimCol, GetDate()) = 0
 
--下月
 
Select * From TableName Where DateDiff(mm, GetDate(), DateTimCol ) = 1
 
--------------------------------------------------------
 
--本周
 
select * from tb where datediff(week , 时间字段 ,getdate()) = 0
 
--上周
 
select * from tb where datediff(week , 时间字段 ,getdate()) = 1
 
--下周
 
select * from tb where datediff(week , 时间字段 ,getdate()) = -1