SQL语句修改字段类型报错

Sybase 12.5数据库执行

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alter?? table????test01 ?modify????username ?varchar(35) null

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alter?? table????test01 ?modify????username ?varchar(15) null

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执行两遍后会报错 如下图

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则需要打开 select into 的权限 ，如下图

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所以如果要动态修改Sybase的字段类型，需要先判断改字段的类型是否需要修改

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select      a.name as 字段名,  b.name as 字段类型,   a.length as 长度,  (case  when  a.status =8  then 'null'  else 'not mull'  end) as  是否为空,  isnull(e.text,'')  as 默认值 FROM     syscolumns     a   left   join   systypes   b        on     a.usertype=b.usertype    inner   join   sysobjects   d        on   a.id=d.id     and     d.type='U'   and     d.name<>'dtproperties'   left   join   syscomments   e      on   a.cdefault=e.id    where d.name='表名

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