Postgresql 选择常量
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时间：2020-10-21 02:11:07 来源:igfitidea点击:
Postgresql Select Constant
提问by Brett Brockway
In Oracle I can select a constant value that will populate down the column like this:
在 Oracle 中，我可以选择一个常量值来填充列，如下所示：
Select
"constant" constantvalue,
orders.name
from
orders
and it will yield:
它会产生：
ConstantValue Name
constant sandwich
constant burger
For whatever reason, when I try to do this in postgres I receive this error.
无论出于何种原因，当我尝试在 postgres 中执行此操作时，我收到此错误。
ERROR: column "Constant" does not exist
here is my code
这是我的代码
select
date_trunc('day', measurement_date + (interval '1 day' * (6 - extract(dow from measurement_date)))) week,
"AROutstanding" colname,
round(avg(Total_Outstanding),0) numbah
from
(
select
measurement_date,
sum(cast(sum_of_dollars as numeric)) Total_Outstanding
from
stock_metrics
where
invoice_status not in ('F','Write off')
group by
measurement_date
) tt
group by
week
回答by Adrian Lynch
Change your double quotes to single quotes.
将双引号更改为单引号。
So this:
所以这：
Select
"constant" constantvalue,
orders.name
from
orders
Should be this:
应该是这样的：
Select
'constant' constantvalue,
orders.name
from
orders
