sqlserver两表之间如何更新全部数据

create table A(
Id int identity(1,1) primary key,
Num varchar(200) unique,
type2 varchar(200),
type1 varchar(200),
caozuo varchar(200),
yuzhanmen varchar(200),
begintime varchar(200),
endtime varchar(200),
compony varchar(200),
manageMan varchar(200),
isTrought varchar(200),
useCompony varchar(200)
)

A 表和B表结构相同 ID自增

SQL code

truncate table B
set IDENTITY_INSERT ON
insert into B select * from A
set IDENTITY_INSERT OFF