Question

我的tsql数据表中有一个表：

CREATE TABLE dbo.Test
(
     Col nVarChar (50) null
)
GO

然后我执行了查询：

Select 
    c.name As Name, ty.name as Type, c.max_length As MaxLenght, c.precision As Precision, c.scale As Scale, c.is_nullable As IsNullable, *
From
    sys.schemas s
    inner join sys.tables t on s.schema_id = t.schema_id
    inner join sys.columns c on t.object_id = c.object_id
    inner join sys.types ty on ty.system_type_id = c.system_type_id
Where
    s.name LIKE 'dbo' AND t.name LIKE 'Test'

问题是......为什么有Two Rows？！

Answer 1

检查一下：

SELECT ROW_NUMBER() OVER(PARTITION BY system_type_id ORDER BY system_type_id)
      , *
FROM sys.types;

检查第一列的值＆gt; 1 ...

映射到同一system_type_id的类型很少。某些名称只是别名的其他内容......

更新

This question解决了同样的问题......

TSQL - 为什么在创建nVarChar列时会创建sysname？

1 个答案:

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