能否在程序运行的过程中修改数据库字段类型？分数不够再加

[xjtu11yao]

我有个“代号”字段，是文本型，想在运行的时候修改为数字型。
运行完后再改回来。（因为程序别的地方需要这个字段为文本型）
可以改么？

[smilejiangjun]

这样改数据库是没有意义的
而且这样的转换会让你的数据库丢失数据

建议你将文本取出来变成数字形式用

[zw_yu]

如果这个字段里有文本内容，你怎么改也不会成功的
文本就是文本，便不成数字的
想想其他办法吧

愚见

[dsclub]

因为程序别的地方需要这个字段为文本型
//////////////////////////

改字段类型干什么呢。
就在需要的地方把取出的值转成String嘛…………

[yefm]

ALTER TABLE
通过更改、添加、除去列和约束，或者通过启用或禁用约束和触发器来更改表的定义。

语法
ALTER TABLE table
{ [ ALTER COLUMN column_name
{ new_data_type [ ( precision [ , scale ] ) ]
[ COLLATE < collation_name > ]
[ NULL | NOT NULL ]
| {ADD | DROP } ROWGUIDCOL }
]
| ADD
{ [ < column_definition > ]
| column_name AS computed_column_expression
} [ ,...n ]
| [ WITH CHECK | WITH NOCHECK ] ADD
{ < table_constraint > } [ ,...n ]
| DROP
{ [ CONSTRAINT ] constraint_name
| COLUMN column } [ ,...n ]
| { CHECK | NOCHECK } CONSTRAINT
{ ALL | constraint_name [ ,...n ] }
| { ENABLE | DISABLE } TRIGGER
{ ALL | trigger_name [ ,...n ] }
}

< column_definition > ::=
{ column_name data_type }
[ [ DEFAULT constant_expression ] [ WITH VALUES ]
| [ IDENTITY [ ( seed , increment ) [ NOT FOR REPLICATION ] ] ]
]
[ ROWGUIDCOL ]
[ COLLATE < collation_name > ]
[ < column_constraint > ] [ ...n ]

< column_constraint > ::=
[ CONSTRAINT constraint_name ]
{ [ NULL | NOT NULL ]
| [ { PRIMARY KEY | UNIQUE }
[ CLUSTERED | NONCLUSTERED ]
[ WITH FILLFACTOR = fillfactor ]
[ ON { filegroup | DEFAULT } ]
]
| [ [ FOREIGN KEY ]
REFERENCES ref_table [ ( ref_column ) ]
[ ON DELETE { CASCADE | NO ACTION } ]
[ ON UPDATE { CASCADE | NO ACTION } ]
[ NOT FOR REPLICATION ]
]
| CHECK [ NOT FOR REPLICATION ]
( logical_expression )
}

< table_constraint > ::=
[ CONSTRAINT constraint_name ]
{ [ { PRIMARY KEY | UNIQUE }
[ CLUSTERED | NONCLUSTERED ]
{ ( column [ ,...n ] ) }
[ WITH FILLFACTOR = fillfactor ]
[ ON { filegroup | DEFAULT } ]
]
| FOREIGN KEY
[ ( column [ ,...n ] ) ]
REFERENCES ref_table [ ( ref_column [ ,...n ] ) ]
[ ON DELETE { CASCADE | NO ACTION } ]
[ ON UPDATE { CASCADE | NO ACTION } ]
[ NOT FOR REPLICATION ]
| DEFAULT constant_expression
[ FOR column ] [ WITH VALUES ]
| CHECK [ NOT FOR REPLICATION ]
( search_conditions )
}

[lxcc]

在需要的地方，对“代号”字段进行转化
例如：
dim iNum as integer
iNum = clng(rs("sNum"))