Django聚合带有表达式的查询

在SQL中，您想要的实际上是

SELECt x/y, * FROM XYZ ORDER BY x/y DESC LIMIT 1;# Or more verbose version of the #1SELECt x/y, id, a, b, x, y FROM XYZ GROUP BY x/y, id, a, b, x, y ORDER BY x/y DESC LIMIT 1;# OrSELECt * FROM XYZ WHERe x/y = (SELECt MAX(x/y) FROM XYZ) LIMIT 1;

因此，在Django ORM中：

XYZ.objects.extra(select={'z':'x/y'}).order_by('-z')[0]# OrXYZ.objects.extra(select={'z':'x/y'}).annotate().order_by('-z')[0]# Or x/y=z => x=y*zXYZ.objects.filter(x=models.F('y') * XYZ.objects.extra(select={'z':'MAX(x/y)'})[0].z)[0]

版本号

XYZ.all().extra(select={'z':'MAX(x/y)'})[0].z

因为没有正确的X，Y和实例

MAX

GROUPBY

z

MAX(x/y)