MySQL (C API)VC实例及代码下载 (1)(5)
修改别人的,需要sysadmin role
EXEC sp_password NULL, 'newpassword', 'User'
如果帐号为SA执行EXEC sp_password NULL, 'newpassword', sa
11.5. 怎么判断出一个表的哪些字段不允许为空?
select COLUMN_NAME from INFORMATION_SCHEMA.COLUMNS where IS_NULLABLE='NO' and TABLE_NAME=tablename
11.6. 如何在数据库里找到含有相同字段的表?
a. 查已知列名的情况
SELECT b.name as TableName,a.name as columnname
From syscolumns a INNER JOIN sysobjects b
ON a.id=b.id
AND b.type='U'
AND a.name='你的字段名字'
b. 未知列名查所有在不同表出现过的列名
Select o.name As tablename,s1.name As columnname
From syscolumns s1, sysobjects o
Where s1.id = o.id
And o.type = 'U'
And Exists (
Select 1 From syscolumns s2
Where s1.name = s2.name
And s1.id s2.id
)
11.7. 查询第xxx行数据
假设id是主键:
select *
from (select top xxx * from yourtable) aa
where not exists(select 1 from (select top xxx-1 * from yourtable) bb where aa.id=bb.id)
如果使用游标也是可以的
fetch absolute [number] from [cursor_name]
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