修改字段名
Exec sp_rename 'zxchem_Suggest.End_Date','Yj_Finish_Date','Column'
修改字段长度
Alter Table zxchem_Suggest Alter Column Yj_Finish_Date Varchar(10) Not Null
增加字段
alter table docdsp add dspcode char(200)
删除字段
ALTER TABLE table_NAME DROP COLUMN column_NAME
修改字段类型
ALTER TABLE table_name ALTER COLUMN column_name new_data_type
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