擅长:python、mysql、java
<p>如果航空公司是金融数据的外键,那么航空公司与金融数据之间存在一对多的关系。它意味着:</p>
<pre><code> obj = Airline.objects.get(pk=3)
</code></pre>
<p>只会给你一个对象。这个对象有许多附加的财务数据,你可以通过说:</p>
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<p>一旦你有了以pk为参数的观点,就可以从财务数据中查询航空公司,反之亦然:</p>
<pre><code> def airlinedata(request, pk):
financial = FinancialData.objects.filter(airline__pk=pk)
# Notice the double underscore, it's called field lookup. You can lookup fields in other model from a model using it.
# If u get your airline data first however by using:
airline = Airline.objects.get(pk=pk)
# You can obtain all financial data attached to it thus:
financials = airline.fiancial_data_set.all()
</code></pre>
<p>我希望这有帮助!在</p>