mysql - How to retrieve all of the records which dont have any reference in another table? -

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  तालिकाआ आईडी, नाम 1, एबीसी 2, सीडी 3, डेफ टेबलब आईडी, टेबलएआईडी, विषय 1, 1, Blah 2, 1, blah again 3, 2, abcdef

मैं TableA से उन सभी रिकॉर्ड का चयन करना चाहता हूं जो तालिका में कोई संदर्भ नहीं है I मैं इसे Mysql में कैसे कर सकता हूं?

बहुत बहुत धन्यवाद।

आप कर सकते हैं LEFT JOIN का उपयोग करें और इन रिकॉर्ड का चयन करें, जो बी में मेल नहीं खाते हैं। 

  SELECT TableA। * से टेबल ले जाने से TableB पर TableB.TableA_id = TableA.id जहां TableB.id NULL है

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