php大數(shù)據(jù)量有關(guān)問題,請(qǐng)問
Jun 13, 2016 pm 12:21 PM
php大數(shù)據(jù)量問題,請(qǐng)教
在網(wǎng)站上用戶要下載歷史記錄,有幾百萬條記錄,一旦用戶選擇全部條件搜索后下載,數(shù)據(jù)庫和服務(wù)器就好像掛掉了,請(qǐng)問有哪些方法可以解決這類問題?
------解決思路----------------------
php打包,分割成幾個(gè)文件,最后zip下載。
點(diǎn)擊下載后,異步處理,后臺(tái)啟動(dòng)一個(gè)php進(jìn)程處理,避免服務(wù)器受到影響。
------解決思路----------------------
數(shù)據(jù)庫做個(gè)主從,這種查詢就直接走從數(shù)據(jù)庫好了,如果實(shí)時(shí)性?不強(qiáng)的話,也可以考慮在空閑時(shí)段打包好(可以增量打包如果用戶可接受的話)提供給用戶下載,
最重要的一點(diǎn)?優(yōu)化你下載的程序。
------解決思路----------------------
這取決于你打算將什么樣格式的數(shù)據(jù)給用戶
如果是在查詢后逐條組裝,顯然是很慢的
如果格式比較簡單,可用?INTO?OUTFILE?子句直接將查詢結(jié)果保存于文件。再將該文件的連接發(fā)給用戶
INTO?OUTFILE?子句默認(rèn)產(chǎn)生的文件是以?Tab?做字段分隔符(很普通的?csv?格式),當(dāng)然你還可以指定
INTO?OUTFILE?產(chǎn)生的文件,可以用?LOAD?DATA?INFILE?指令導(dǎo)回表中。
不失為一種數(shù)據(jù)備份的方法

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