query performance - How to cast MySQL result to a string? -

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एक क्वेरी है: 

  blatable WHERE blafield = 714 से चुनें blalist

जो ऐसा स्ट्रिंग देता है जो दिखता है: "2,12,29,714,543,171 9" और एक अन्य क्वेरी है: 

  का चयन करें userid, नाम, उपनाम, क्रेडिट कार्डनाम, चुराके से आइटम जहां यूज़र आईडी में (blatable WHERE blafield = 714 से चुनें blalist)
< P> अब वह काम नहीं कर रहा है
मैं केवल इन प्रश्नों को अलग से निष्पादित करके काम करने में कामयाब रहा हूं। मुझे इसे एक सिंगल क्वेरी में रखने के लिए क्या करना चाहिए?

आपको एक से अधिक मूल्य को कभी भी संग्रहीत नहीं करना चाहिए एक कोशिका blatable में प्रत्येक मान अपनी ही पंक्ति में होना चाहिए, फिर आपका IN खंड एक जादू की तरह काम करेगा डेटाबेस सामान्यीकरण पर एक नज़र डालें और विशेष रूप से आपकी तालिकाओं को कैसे डिज़ाइन किया जाना चाहिए।

जैसा कि आपके पास एक सेल में सभी मान हैं, सभी कोडों में IN तुलना के परिणाम स्ट्रिंग "2,12,29,714,543,171 9" की तुलना में, जो स्पष्ट रूप से मेल नहीं खाएगा। आपकी क्वेरी प्रभावी ढंग से इस तरह दिखती है: 

  ... चुराके से जहां यूजर आईडी IN ("2,12,29,714,543,171 9")

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