Sql 将日期从一个表复制到其他表的最佳方法

我有这张桌子：

身份证件 名字 角色 1 汤姆 行政 2 汤姆 使用者 三 约翰 行政 您可以使用以下查询：

insert into user (name)
    select distinct name
    from following;

insert into userrole (userid, roleid)
    select u.userid, f.roleid
    from following f join
         user u
         on f.name = u.name;

---

这些可以合并到存储过程中。

您也可以尝试合并添加、更新和删除。Merge使用复合索引或主键查找匹配行。这是etl的一种数据仓库方式。您可能必须将主键的标识设置为off

use MyDataDB

declare @Output as varchar(max)
declare @ColumnName as varchar(100)
declare @TableName as varchar(30)='your_table_name'
declare @UpdateStatement as varchar(max)=''
declare @InsertStatement as varchar(max)=''
declare @InsertStatement2 as varchar(max)=''
declare @DeleteStatement as varchar(max)=''

Declare @Join as varchar(max)
declare @JoinColumns Table(ColumnName varchar(50))

---- Add your primary Key here or composite index
Insert into @JoinColumns(ColumnName) 
values('YourKeyID')

select @Join=
(select ' AND TARGET.'+ColumnName+'=SOURCE.'+ColumnName from @JoinColumns for xml path('')) 

select @Join=right(@Join,len(@Join)-5)

declare c1 cursor
for
SELECT
COLUMN_NAME
FROM
INFORMATION_SCHEMA.COLUMNS
WHERE
TABLE_NAME = @TableName


open c1

fetch next from c1 into @ColumnName
set @Output=N'MERGE ReportData.dbo.'+ @TableName + '  as TARGET USING ReportData.dbo.' + @TableName + '_Stage as SOURCE ON 
  (' + @Join +')    WHEN MATCHED THEN ';

set @UpdateStatement=N' UPDATE SET ';

set @InsertStatement =N' WHEN NOT MATCHED BY TARGET THEN INSERT(';
set @InsertStatement2=N' Values(';

set @DeleteStatement=N' WHEN NOT MATCHED BY SOURCE THEN DELETE';

while @@FETCH_STATUS=0
    begin
    if not exists(select '' from @JoinColumns where ColumnName=@ColumnName)
    begin
        if @UpdateStatement=N' UPDATE SET ' 
                SET @UpdateStatement=@UpdateStatement + 'TARGET.' + @ColumnName+'='+'SOURCE.'+@ColumnName 
        else
                SET @UpdateStatement=@UpdateStatement + ',TARGET.' + @ColumnName+'='+'SOURCE.'+@ColumnName
    end
    if @InsertStatement =N' WHEN NOT MATCHED BY TARGET THEN INSERT('
        BEGIN
            Set @InsertStatement=@InsertStatement+@ColumnName
            Set @InsertStatement2=@InsertStatement2+'SOURCE.'+@ColumnName
        END
    ELSE
        BEGIN
            Set @InsertStatement=@InsertStatement+','+@ColumnName
            Set @InsertStatement2=@InsertStatement2+',SOURCE.'+@ColumnName
        END
        
    fetch next from c1 into @ColumnName
end
close c1
deallocate c1
SET @Output=@Output + @UpdateStatement
SET @Output=@Output + @InsertStatement+') '
SET @Output=@Output + @InsertStatement2+') '
SET @Output=@Output + @DeleteStatement+';'

select @Output