Mysql ninja tricks -

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संभव डुप्लिकेट:

हाय,

आपका माइस्केल निंजा ट्रिक्स क्या हैं? क्या विशेषताएं अतिरिक्त विशेष हैं?

मैं ORDER BY FIELD से शुरू कर रहा हूं, जिससे आप किसी विशेष क्रम में सॉर्ट कर सकते हैं, जैसे: 

  ग्राहक से ORDER द्वारा FIELD (customer.priority, 1, 2, 3, 0) से यूआरएल का चयन करें

इस तरह की विशेषताएं mysql दस्तावेज़ीकरण में खोजना कठिन है।

इसे लाओ!

क्वेरी निष्पादन योजना को प्रोफाइल करने के लिए EXPLAIN का उपयोग करें

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