Question

在我的models.py中，我有两个模型：

class Well(models.Model):
    id = models.AutoField(db_column='ID', primary_key=True, verbose_name='DNS') 
    block = models.ForeignKey(Block, db_column='Block_ID', verbose_name='Block')
    uwi = models.CharField(db_column='UWI', max_length=20, blank=True, verbose_name='UWI') 
    welllocation = models.ForeignKey('Welllocation', db_column='WellLocation_ID', verbose_name='Location')
    # Plus a number of other columns

class Welldrillingdetails(models.Model):
    id = models.AutoField(db_column='ID', primary_key=True, verbose_name='DNS') 
    well = models.ForeignKey(Well, db_column='Well_ID', verbose_name='Well') 
    casingdetails = models.ForeignKey(Casingdetails, db_column='CasingDetails_ID', verbose_name='Casing Name')
    holesize = models.CharField(db_column='holeSize', max_length=15, blank=True, verbose_name='Hole Size (inch)')
    # Plus a number of other columns

表Welldrillingdetails使用pk表Well作为外键。我有一个python字典，其中包含一个元素列表，其中列出了我从JSON转换的well表的主键。

raw_data = {"wells": [1,2], "seams": ["2"], "tables": [{"name": "Well", "fields": []}, {"name": "Stratigraphy", "fields": []}]}

当我使用：

获取Welldrillingdetails模型的对象时

ObjList.append(Welldrillingdetails.objects.all().filter(well__in=raw_data['wells']))

工作正常。但是当我使用：{/ p>为Well表执行相同操作时

ObjList.append(Well.objects.in_bulk(raw_data['wells']))

或

ObjList.append(Well.objects.all().filter(id__in=raw_data['wells']))

或

ObjList.append(Well.objects.all().filter(pk__in=raw_data['wells']))

它不起作用并给出错误：

FieldError at /cbm/ajaxp/display_data/
Cannot resolve keyword 'well' into field. Choices are: ai, artificiallifts, block, category, coalseamdisp, coalseamseval, coredata, desorbedgascomp, dewateringdetails, drillcompletedate, drilleddepth, electrologs, gc, gl, hermtestingdate, hydrofracdata, id, kb, latitude, loggerdepth, longitude, maceral, minifractestresults, normalisedgc, objective, observations, pmrockprop, presentstatus, profile, projecteddepth, proximate, ptobjectinterval, releaseorderdate, releaseorderno, reserviorwelltestdata, rigname, rigreleasedate, spuddate, stratigraphy, toc, toposheet, triaxialstrength, ultimate, uwi, wcrfile, welldrillingdetails, welllocation, welltype

使用主键获取时语法是否不同？

Answer 1

首先在关系中使用related_name，它可以帮助您更好地确定和识别反向关系。

class Well(models.Model):
    id = models.AutoField(db_column='ID', primary_key=True, verbose_name='DNS') 
    block = models.ForeignKey(Block, db_column='Block_ID', verbose_name='Block', related_name="well")
    uwi = models.CharField(db_column='UWI', max_length=20, blank=True, verbose_name='UWI') 
    welllocation = models.ForeignKey('Welllocation', db_column='WellLocation_ID', verbose_name='Location', related_name="well")
    # Plus a number of other columns

class Welldrillingdetails(models.Model):
    id = models.AutoField(db_column='ID', primary_key=True, verbose_name='DNS') 
    well = models.ForeignKey(Well, db_column='Well_ID', verbose_name='Well', related_name='drillingdetails') 
    casingdetails = models.ForeignKey(Casingdetails, db_column='CasingDetails_ID', verbose_name='Casing Name', related_name="drillingdetails")
    holesize = models.CharField(db_column='holeSize', max_length=15, blank=True, verbose_name='Hole Size (inch)')
    # Plus a number of other columns

批量无效，因为您的列表实际上未通过：

ObjList.append(Well.objects.in_bulk(list(raw_data['wells'])))

如果上述情况未再次评估，请在通话前强制执行列表：

well_ids = list(raw_data["wells"])
ObjList.append(Well.objects.in_bulk(well_ids))

使用上面的reverse_relation，您还可以：

ObjList.append(Welldrillingdetails.objects.select_related('well').filter(well__in=raw_data['wells']))

Answer 2

实际上，您的查询是正确的，这个问题肯定会有效：

ObjList.append(Well.objects.all().filter(pk__in=raw_data['wells']))

我认为问题出在ObjList，我怀疑它不是正常的列表。来自您的错误报告

FieldError at /cbm/ajaxp/display_data/
Cannot resolve keyword 'well' into field. Choices are: ai, artificiallifts, block, category, coalseamdisp, coalseamseval, coredata, desorbedgascomp, dewateringdetails, drillcompletedate, drilleddepth, electrologs, gc, gl, hermtestingdate, hydrofracdata, id, kb, latitude, loggerdepth, longitude, maceral, minifractestresults, normalisedgc, objective, observations, pmrockprop, presentstatus, profile, projecteddepth, proximate, ptobjectinterval, releaseorderdate, releaseorderno, reserviorwelltestdata, rigname, rigreleasedate, spuddate, stratigraphy, toc, toposheet, triaxialstrength, ultimate, uwi, wcrfile, welldrillingdetails, welllocation, welltype

看起来ObjList具有welldrillingdetails属性但缺少well。我的猜测是ObjList以某种方式将您要追加的模型的类名转换为属性名称，并且缺少well属性。

Django使用主键列表来获取记录

2 个答案: