mysql - 将 sql 查询结果的前 4 个字符分配到另一列？

Question

我正在使用下面的 SQL 代码来获取计算机列表。我需要以某种方式获取这些结果并用每条记录的前 4 个字符填充它旁边的另一列。例如:

Computer Name  New Column

ABCD1000P      ABCD

这可能吗？

SELECT   SYS.Netbios_Name0
FROM dbo.v_R_System AS SYS 
     INNER JOIN dbo.v_GS_PROCESSOR AS Processor ON SYS.ResourceID = Processor.ResourceID 
     INNER JOIN dbo.v_GS_COMPUTER_SYSTEM ON SYS.ResourceID = dbo.v_GS_COMPUTER_SYSTEM.ResourceID
WHERE (SYS.Obsolete0 = 0) AND (SYS.Client0 = 1)and SYS.Netbios_Name0 not like '%-%'

Answer 1

使用LEFT函数

SELECT S.Netbios_Name0 AS ComputerName, LEFT(S.Netbios_Name0, 4) AS NewColumn
FROM dbo.v_R_System AS S
INNER JOIN dbo.v_GS_PROCESSOR AS P ON S.ResourceID = P.ResourceID 
INNER JOIN dbo.v_GS_COMPUTER_SYSTEM AS C ON S.ResourceID = C.ResourceID
WHERE S.Obsolete0 = 0
AND S.Client0 = 1
AND S.Netbios_Name0 NOT LIKE '%-%'