英文:
Can I use "/" operator on nvarchar column type in SQL Server Management Studio?
问题
我试图将两列进行除法运算，这两列被定义为nvarchar，但是SQL Server Management Studio(SSMS)抛出错误，指出无法在nvarchar上使用/运算符。
select
location, date, total_cases, total_deaths,
(total_deaths / total_cases) * 100
from
CovidDeaths#xlsx$
order by
1, 2
我无法对total_cases和total_deaths进行除法运算。
英文:
I am trying to divide 2 columns which are defined as nvarchar, but SSMS throws an error saying you can not use / operator on nvarchar.
select
location, date, total_cases, total_deaths,
(total_deaths / total_cases) * 100
from
CovidDeaths#xlsx$
order by
1, 2
I am unable to divide the total_cases and total_deaths.
答案1
得分: 2
请尝试以下更改，因为您无法将 "string" 值进行除法运算。请考虑将其转换或强制转换为十进制值。我假设我的回答中的 total_cases 不为零。
select
location,
date,
total_cases,
total_deaths,
CONVERT(DECIMAL(18, 2), (CONVERT(DECIMAL(18, 2), total_deaths) / CONVERT(DECIMAL(18, 2), total_cases))) as [DeathsOverTotal]
from CovidDeaths#xlsx$
order by 1,2
英文:
Try the following instead since you cannot divide "string" values. Consider converting or casting to a decimal value. I'm assuming total_cases is nonzero in my answer.
select
location,
date,
total_cases,
total_deaths,
CONVERT(DECIMAL(18, 2), (CONVERT(DECIMAL(18, 2), total_deaths) / CONVERT(DECIMAL(18, 2), total_cases))) as [DeathsOverTotal]
from CovidDeaths#xlsx$
order by 1,2
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论