Mssql 删除自增主键约束，添加默认值为序列器生成值

alter table MODEL_COLLECT add temp_colum bigint default (NEXT VALUE FOR SEQ_MODEL_COLLECT) not null;
go
update MODEL_COLLECT set temp_colum=MC_CODE ;
go

--删除默认值约束
declare @name varchar(100) 
select @name=b.name from syscolumns a,sysobjects b where a.id=object_id('MODEL_COLLECT') and b.id=a.cdefault and a.name='MC_CODE' and b.name like 'DF%' 
IF @name<>''
BEGIN
exec('alter table MODEL_COLLECT drop constraint '+@name) 
END

alter table MODEL_COLLECT drop column MC_CODE ;
go
exec sp_rename 'MODEL_COLLECT.temp_colum', 'MC_CODE', 'COLUMN';
go

转载自：https://blog.csdn.net/baidu_36415076/article/details/53193013