sql - The Quantity of things in one table -


मेरे पास दो अलग-अलग टेबल हैं

  • कुत्तों (आईडी, नाम) < / P>

  • dogs_pref (id_dog, वरीयता (केवल एक))

  • प्राथमिकताएं (एक कुत्ते में 0, 1, 2 प्राथमिकताएं हो सकती हैं

    यह कार्य दो अलग-अलग अनुरोधों का निर्माण कर रहा है

    1: अनुरोध जो कुत्तों को वरीयताओं से दिखाता है (एक या दो से अधिक) 2: बनाएं

    1: 

      SELECT dogs.Name, dogs_pref.id_dog, dogs_pref.preference। कुत्ते को छोड़ने से कुत्ते को छोड़ दें dogs_pref ON dogs.Id = Dogs_pref.id_dog जहां dogs_pref.preference> gt; = 1 ORDER द्वारा dogs.Id;   
     2:  
     यहां सबसे बड़ा सवाल है कि इसे कैसे सरल तरीके से लिखना है ????   
     
     
      चुनें dogs.id, sum (to_number (dogs_pref.preference)) कुत्तों से छोड़ें dogs_pref ON dogs.Id = dog_pref.id_dog समूह dogs.id द्वारा ;

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