Question

连接到Oracle数据库，我需要运行以下查询：

SELECT
    ad_campaign_id as campaign_id,
    TO_DATE("DAY", 'YYYY-MM-DD') as DAY,
    NVL(spent, 0) as spent,
    impressions,
    clicks 
FROM sometable

我如何使用SQLAlchemy执行此操作？如何将参数发送到func.to_date函数？

Answer 1

SQLAlchemy的 func 将接受任何Oracle函数作为属性。

from sqlalchemy import func

campaign_id = sometable.c.ad_campaign_id
day = func.to_date(sometable.c.day, 'YYYY-MM-DD') # Is this what you need?
spent = func.nvl(sometable.c.spent, 0)
clicks = sometable.c.clicks
cols = [campaign_id, day, spent, clicks]

# Feel free to skip, this is just so you get the labels you want
labels = "campaign_id day spent clicks".split()
col_label = zip(cols, labels)
labelled = [c.label(l) for (c,l) in col_label]

q = session.query(*labelled) # or use *cols if you don't care about labels
q.all()

Answer 2

以下是执行任意查询的方法：

engine.execute(query_string)

设置引擎是另一回事。尽管如此，它还是有很好的记录。

如果你问的是如何使用某个不同故事的模型来做到这一点......

这样你问题的第一部分（可能）得到了解答。但你的func.to_date函数是什么意思？请澄清

sqlalchemy选择to_date

2 个答案: