I have this query:
mps = (
session.query(mps) .filter_by(idc = int(c.idc))
.filter_by(idmp = int(m.idmp))
.group_by(func.day(mps.tschecked))
).all()
My probl开发者_如何学Goem is, that I don't know how to extract (with sqlalchemy) the max/min/avg value from a table...
I find this: Database-Independent MAX() Function in SQLAlchemy
But I don't know where to use this func.max/min/avg...
Can someone tell me how to do this? Can you give me an example?
The following functions are available with from sqlalchemy import func
:
func.min
func.max
func.avg
Documentation is available here.
You can use them i.e. in the query() method.
Example:
session.query(self.stats.c.ID, func.max(self.stats.c.STA_DATE))
(just like you use aggregate functions in plain SQL)
Or just use an order_by() and select the first or last element. . .
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