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HomeDatabaseMysql TutorialSQL中object_id函数的用法

SQL中object_id函数的用法

在列出表中所有字段名的时候,用到了这样一个SQL函数:object_id
这里我将其作用与用法列出来,好让大家明白:

OBJECT_ID:
返回数据库对象标识号。

语法
OBJECT_ID ( 'object' )

参数
'object'

要使用的对象。object 的数据类型为 char 或 nchar。如果 object 的数据类型是 char,那么隐性将其转换成 nchar。

返回类型
int

注释
当该参数对系统函数可选时,则系统采用当前数据库、主机、服务器用户或数据库用户。内置函数后面必须跟圆括号。

如果指定一个临时表名,则必须在临时表名前面加上数据库名,例如:

SELECT OBJECT_ID('tempdb..#mytemptable')

系统函数可以在选择列表、WHERE 子句和任何允许使用表达式的地方使用。有关更多信息,请参见表达式和 WHERE。

示例
下面的示例为 pubs 数据库中的 authors 表返回对象 ID。

USE master
SELECT OBJECT_ID('pubs..authors')

下面是结果集:

-----------
1977058079

(1 row(s) affected)
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