添加列:
ADD column_name datatype
ADD s_status bit
为列添加默认值:
1,在添加列时,添加默认值:
ADD column_name datatype default(value)
ADD s_status bit default(0)
2,用给列添加约束的方式添加:
ADD CONSTRAINT [DF_name] default(value) FOR column_name
ADD CONSTRAINT [DF_status] default(1) FOR s_status
更改列的数据类型:
ALTER COLUMN column_name datatype
ALTER COLUMN s_status nchar(16)
删除列:
DROP COLUMN column_name
DROP COLUMN s_status