Question

这是一个问题：从Person Table中选择BusinessEntityID，Title，First Name的第一个字母，MiddleName的第一个字母和Last Name（标签为Full Name），其中任何部分都没有NULL名称。

这就是我到目前为止：

 Use AdventureWorks2008R2;
    Select BusinessEntityID,SUBSTRING(Title,1,3)+' '+SUBSTRING(FirstName,1,1)+' '+
    SUBSTRING(MiddleName,1,1)+' '+ LastName as 'Full Name'
    From Person.Person
    Where LastName IS NOT NULL;

但LastName列显示NULL值

Answer 1

如果您连接在一起的任何列为NULL，则结果将为NULL。您还必须过滤掉Title，FirstName和MiddleName。

Use AdventureWorks2008R2;
SELECT BusinessEntityID,SUBSTRING(Title,1,3)+' '+SUBSTRING(FirstName,1,1)+' '+
SUBSTRING(MiddleName,1,1)+' '+ LastName as 'Full Name'
From Person.Person
Where LastName IS NOT NULL AND
      Title IS NOT NULL AND 
      FirstName IS NOT NULL AND
      MiddleName IS NOT NULL;

Answer 2

您可以执行以下操作：

Use AdventureWorks2008R2;
Select BusinessEntityID,SUBSTRING(Title,1,3)+' '+SUBSTRING(FirstName,1,1)+' '+
SUBSTRING(MiddleName,1,1)+' '+ LastName as 'Full Name'
From Person.Person
Where LastName IS NOT NULL AND LastName != ''

其中<column name =“”>不为空</column>

2 个答案: