mysql - How do I GROUP BY and then LEFT JOIN? -

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इस सवाल का पहले से ही एक उत्तर है: < / P>

  • 9 जवाब

मेरे पास यह है तालिका: 

  ------------------ | आईडी | खाद्य पदार्थ | ------------------ | 1 | कुकीज़ | | 2 | केक | | 3 | दूध | ------------------

और यह तालिका: 

  ------------------ | आईडी | रंग | ------------------ | 1 | लाल | | 1 | नीला | | 1 | गुलाबी | | 2 | नारंगी | | 2 | पीला | | 2 | बैंगनी | | 3 | सियान | | 3 | सोना | | 3 | चांदी | ------------------

मैं पहली तालिका से खाद्य पदार्थों का चयन करना चाहता हूं और उन्हें दूसरी तालिका से रंगों से मेल करना चाहता हूं, आईडी पर आधारित।

इसलिए मुझे आउटपुट को इस तरह दिखना चाहिए: 

  ------------ -------------------------------- | आईडी | खाद्य पदार्थ | रंग | -------------------------------------------- | 1 | कुकीज़ | लाल, नीला, गुलाबी | | 2 | केक | नारंगी, पीले, बैंगनी | | 3 | दूध | सियान, सोना, चांदी | --------------------------------------------   
 मैं यह कैसे कर सकता हूं? 
 
  संपादित करें: यह एक डुप्लिकेट नहीं है। मैं सम्मिलित करने की कोशिश नहीं कर रहा हूं मैं एक संयुक्त तालिका को आईडी पर आधारित एक नियमित तालिका में मर्ज करने का प्रयास कर रहा हूं।

इस तरह से कुछ देखो:

<पूर्व> SELECT f.food, GROUP_CONCAT (c.color SEPARATOR '') से food_table f में color_table सी में जोड़ें f.food_id = c.id ग्रुप द्वारा भोजन;

दस्तावेज़ीकरण यहां पाया जा सकता है:


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