选择整数

Question

我有一个SQL Server表（“Activities”），它有一个包含ID的列，例如“10553100”。这是活动ID，由两部分组成 - ＆gt;前4位数字表示它属于哪个项目，后4位数字表示哪个子项目。

我需要从activityId列（也就是前4位）中提取项目编号。是否可以在SQL中使用简单的SELECT语句来执行此操作？

Answer 1

使用LEFT功能。

SELECT activityId, LEFT(activityId, 4) AS projectnumber
FROM Activities

或SUBSTRING功能。

SELECT activityId, SUBSTRING (activityId, 1, 4) AS projectnumber
FROM Activities

如果你想要包括你的子项目编号

LEFT和RIGHT函数。

SELECT activityId, LEFT(activityId, 4) AS projectnumber, RIGHT(activityId, 4) AS subprojectnumber
FROM Activities

SUBSTRING功能。

SELECT activityId, SUBSTRING (activityId, 1, 4) AS projectnumber, SUBSTRING(activityId, 5, 4) AS subprojectnumber
FROM Activities

Answer 2

select activity_id / 10000 as project
from activities

Answer 3

试试这样：

SELECT CAST(LEFT(ActivityId, 4) AS INT) FROM activities

Answer 4

试试这个

Select left(activityId,4) from Activities

Answer 5

如果字段是数字，则：

SELECT Col / 10000 FROM TableName

如果char：

SELECT LEFT(Col, 4) FROM TableName

Answer 6

左命令你可以工作：

SELECT LEFT(id, 4) FROM dbo.Activities