🌏【架構師指南】總結分庫分表的實現方案

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第二種:網絡IO瓶頸,請求的數據太多,網絡帶寬不夠 ->分庫","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"CPU瓶頸","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":" ","attrs":{}},{"type":"text","marks":[{"type":"color","attrs":{"color":"#F5222D","name":"red"}},{"type":"strong","attrs":{}}],"text":" ","attrs":{}},{"type":"text","marks":[{"type":"size","attrs":{"size":10}},{"type":"color","attrs":{"color":"#000000","name":"black"}},{"type":"strong","attrs":{}}],"text":"第一種:SQL問題,如SQL中包含join,group by,order by,非索引字段條件查詢等,增加CPU運算的操作 -> SQL優化,建立合適的索引,在業務Service層進行業務計算。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"size","attrs":{"size":10}},{"type":"color","attrs":{"color":"#000000","name":"black"}},{"type":"strong","attrs":{}}],"text":" 第二種:單表數據量太大,查詢時掃描的行太多,SQL效率低,CPU率先出現瓶頸 -> 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可以用列表頁和詳情頁來幫助理解。","attrs":{}},{"type":"text","marks":[{"type":"size","attrs":{"size":10}},{"type":"strong","attrs":{}}],"text":"垂直分表的拆分原則是將熱點數據(可能會冗餘經常一起查詢的數據)放在一起作爲主表,非熱點數據放在一起作爲擴展表。","attrs":{}},{"type":"text","marks":[{"type":"size","attrs":{"size":10}}],"text":"這樣更多的熱點數據就能被緩存下來,進而減少了隨機讀IO。拆了之後,要想獲得全部數據就需要關聯兩個表來取數據。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"size","attrs":{"size":10}},{"type":"color","attrs":{"color":"#F5222D","name":"red"}},{"type":"strong","attrs":{}}],"text":" 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