php - Mysql Limit column value repetition N times -

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मेरे पास दो टेबल हैं 

  ग्राहक (idCustomer, ecc .. ecc ..) टिप्पणी (आईडीसी ग्राहक, आईडी कॉममेंट, ईसीसी .. ईसीसी ..)

स्पष्ट रूप से दो तालिकाएं एक साथ जुड़ जाती हैं, उदाहरण के लिए 

  SELECT * FROM टिप्पणी के रूप में सह जॉइन ग्राहक एएस कू ऑन cu.idCustomer = co.idCustomer

इसके साथ मैं उस तालिका से जुड़े सभी टिप्पणी का चयन करता हूं ग्राहक, लेकिन अब मैं टिप्पणी की संख्या को 2 अधिकतम टिप्पणी प्रति सीमित करना चाहता हूँ ग्राहक।

पहली बात मैं देख रहा हूं ग्रुप द्वारा cu.idCustomer का उपयोग करना है, लेकिन यह प्रति ग्राहक केवल 1 टिप्पणी की सीमा है, लेकिन मैं प्रति ग्राहक प्रति 2 टिप्पणी चाहता हूं।

मैं इसे कैसे प्राप्त कर सकता हूं?

MySQL में एक विकल्प सर्वर-साइड वेरिएबल है उदाहरण के लिए: 

  सेट @num: = 0, @customer: = -1; ग्राहक से जुड़ने के साथ * आईडीसी ग्राहक, पोस्टडेट द्वारा दिए गए आदेशों के अनुसार * आईडीसी ग्राहक, टिप्पणी टेक्स्ट, @ नाम: = अगर (@ ग्राहक = आईडीसी ग्राहक, @ 1, 1) को पंक्ति_एनम्बर, @ ग्राहक: = आईडी से चुनें) Co.idCustomer = cu.idCustomer जहां co.row_number & lt; = 2

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