资源介绍
SQL语言教程,入门经典
使用Transact-SQL语句修改表
语法格式：
ALTER TABLE table_name
{ [ALTER COLUMN column_name
{ new_data_type [(precision [, scale])]
[NULL|NOT NULL]
| {ADD|DROP} ROWGUIDCOL } ]
| ADD
{ [ ] | column_name AS computed_column_expression }[ , ... n ]
| [ WITH CHECK | WITH NOCHECK] ADD { } [ , ... n]
| DROP { [CONSTRAINT] constraint_name | COLUMN column_name} [ , ... n]
|{CHECK | NOCHECK} CONSTRAINT {ALL | constraint_name [ , ... n]}
|{ ENABLE | DISABLE } TRIGGER { ALL | trigger_name [ , ... n]}
}