如何将一列插入到 SQL Server 中同一表中的另一列中
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How to insert one column into other column within the same table in SQL Server
提问by kumar
I need to insert one column's data into another column within the same table.
我需要将一列的数据插入同一个表中的另一列。
Can anybody tell me how to write this?
谁能告诉我这个怎么写？
Thanks
谢谢
回答by Cade Roux
UPDATE table
SET col_2 = col_1
回答by Doliveras
If you want to copy data from one column to another on the same table:
如果要将数据从同一表中的一列复制到另一列：
UPDATE table_name SET
destination_column_name=orig_column_name
WHERE condition_if_necessary
IF you want to add a new column and copy the original data to that column:
如果要添加新列并将原始数据复制到该列：
ALTER TABLE table_name
ADD new_column_name column_type NULL
UPDATE table_name SET
destination_column_name=orig_column_name
WHERE condition_if_necessary
回答by Jeffrey L Whitledge
If you want the column to be non-nullable, then you can set it to a default value before doing the update.
如果您希望该列不可为空，则可以在进行更新之前将其设置为默认值。
begin transaction
alter table Song add SortArtist nvarchar(128) not null default N''
go
update Song set SortArtist = Artist
commit transaction
回答by gady RajinikanthB
alter table [dbo].[GetPermission]
add username1 varchar(100) ----------------ading new column username1
更改表 [dbo].[GetPermission]
添加 username1 varchar(100) ----------------ading 新列 username1
update GetPermission set username1=username
更新 GetPermission 设置 username1=用户名
