merge into 目標表 a
using 源表 b
on a.主鍵=b.主鍵 and a.條件字段1=b.條件字段1  ...
when matched update set a.主鍵=b.主鍵,a.字段1=b.字段1 ...
when not matched insert values (b.主鍵,b.字段1 ...)
when not matched by source 
then delete 

CREATE TABLE UserInfo
(
Id uniqueidentifier not null primary key,
LoginName varchar(255) not null,
UserPwd varchar(255) not null CHECK ((len([UserPwd])>=(6)) and (len([UserPwd])<=(64))),
Name varchar(255) not null,
Phone varchar(255) not null,
)

CREATE TABLE UserInfoBase
(
Id uniqueidentifier not null primary key,
LoginName varchar(255) not null,
UserPwd varchar(255) not null CHECK ((len([UserPwd])>=(6)) and (len([UserPwd])<=(64))),
Name varchar(255) not null,
Phone varchar(255) not null,
)

insert into UserInfo(Id, LoginName, UserPwd, Name, Phone)values(LOWER(NEWID()),'admin','123456','管理員','18600000000'),
(LOWER(NEWID()),'admin1','123456','管理員1','18600000000');

merge into UserInfo as a
using UserInfoBase as b on b.ID=b.ID
when matched       --更新 目標表中有ID,則更新
then update set a.[LoginName]=b.[LoginName], a.[UserPwd]=b.[UserPwd],a.[Name]=b.[Name],a.[Phone]=b.[Phone]
when not matched   --添加 目標表中沒有ID,在原表中有，則插入相關數據
then insert values (b.[Id],b.[LoginName],b.[UserPwd],b.[Name],b.[Phone])
when not matched by source --目標表存在，源表不存在，則刪除
then delete;