{"id":100295,"date":"2020-05-01T16:07:03","date_gmt":"2020-05-01T08:07:03","guid":{"rendered":"http:\/\/4563.org\/?p=100295"},"modified":"2020-05-01T16:07:03","modified_gmt":"2020-05-01T08:07:03","slug":"%e8%af%b7%e6%95%99%e4%b8%80%e4%b8%aa-django-orm-%e4%b8%ad%e6%97%a5%e6%9c%9f%e5%ad%97%e6%ae%b5%e5%81%9a%e6%af%94%e8%be%83%e7%9a%84%e9%97%ae%e9%a2%98","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=100295","title":{"rendered":"\u8bf7\u6559\u4e00\u4e2a Django ORM \u4e2d\u65e5\u671f\u5b57\u6bb5\u505a\u6bd4\u8f83\u7684\u95ee\u9898"},"content":{"rendered":"
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\u8bf7\u6559\u4e00\u4e2a Django ORM \u4e2d\u65e5\u671f\u5b57\u6bb5\u505a\u6bd4\u8f83\u7684\u95ee\u9898 <\/h1>\n

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\u8cc7\u6df1\u5927\u4f6c : liulei281 <\/span> <\/i> 60<\/span> <\/div>\n
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\u6709\u8fd9\u6837\u4e00\u4e2a Model:<\/p>\n

class InfoModel:     title = models.CharField('\u6807\u9898', max_length=50)     create_date = models.DateField('\u521b\u5efa\u65e5\u671f', auto_now_add=True)     expiration = models.IntegerField('\u6709\u6548\u671f x \u5929', default=0) <\/code><\/pre>\n
\u8981\u67e5\u8be2\u5f53\u524d\u65f6\u95f4\u70b9\u672a\u8fc7\u671f\u7684\u7684\u6570\u636e.<\/p>\n<\/p><\/div>\n
 \u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (17<\/span>)        <\/div>\n
 <\/div>\n<\/p><\/div>\n<\/p><\/div>\n
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     \u8cc7\u6df1\u5927\u4f6c : chenstack <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u4e3a\u4ec0\u4e48\u4e0d\u5b58\u4e00\u4e2a\u5230\u671f\u65e5\u671f\u7684\u5b57\u6bb5\u5462                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : liulei281 <\/span>  <\/div>\n
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                                                                 @chenstack \u5386\u53f2\u9057\u7559\u95ee\u9898, \u53ea\u80fd\u521a\u6b63\u9762-_-!                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : chenstack <\/span>  <\/div>\n
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                                                                 Django \u7684 F \u8868\u8fbe\u5f0f\u53ef\u4ee5\u5728\u67e5\u8be2\u6216\u66f4\u65b0\u65f6\u5bf9\u5b57\u6bb5\u505a\u52a0\u3001\u51cf\u3001\u4e58\u3001\u9664\u3001\u53d6\u6a21\u548c\u5e42\u8fd0\u7b97\u7b49\u7b97\u672f\u64cd\u4f5c\uff0c\u4f46\u4f60\u7684\u5b57\u6bb5\u662f\u65e5\u671f\u7c7b\u578b\u7684\uff0c\u6ca1\u6709\u8fd9\u6837\u505a\u8fc7\uff0c\u6211\u641c\u5230\u4e86\u7c7b\u4f3c\u8fd9\u6837\u7684\u56de\u7b54 https:\/\/stackoverflow.com\/questions\/38703016\/what-is-the-replacement-for-datemodifiernode-in-new-versions-of-django
    \u665a\u70b9\u6211\u81ea\u5df1\u8bd5\u4e00\u4e0b                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : liulei281 <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @chenstack \u8fd9\u4e9b\u6211\u6628\u5929\u67e5\u4e86\u5f88\u591a, \u6ca1\u627e\u5230\u5408\u9002\u7684\u529e\u6cd5. \u6211\u76ee\u524d\u60f3\u5230\u7684\u89e3\u51b3\u529e\u6cd5:
    InfoModel.objects.annotate(delta=ExpressionWrapper((Value(now().date(), DateField()) – F(‘display_date’)) \/ (24 * 60 * 60 * 1000 * 1000), output_field=IntegerField())).filter(expiration__gte=delta)
    \u770b\u7740\u5f88\u6076\u5fc3…                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : liulei281 <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @chenstack \u5982\u679c\u80fd\u8c03\u7528 Mysql \u7684 CURDATE, TODAYS, INTERVAL \u4e4b\u7c7b\u7684\u65b9\u6cd5\u5c31\u4f1a\u7b80\u5355\u5f88\u591a, \u4f46\u662f\u8c8c\u4f3c django \u4e0d\u652f\u6301                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : SpencerCJH <\/span>  <\/div>\n
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                                                                 @liulei281 \u8c28\u614e\u4f7f\u7528\u8fd9\u4e9b\u51fd\u6570\uff0c\u5728 where \u4e0a\u4e0d\u6b63\u786e\u4f7f\u7528\u4f1a\u8d70\u4e0d\u4e86\u7d22\u5f15\u7684\u5427                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : SjwNo1 <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u8868\u6570\u636e\u91cf\u4e0d\u5927\u5efa\u8bae\u5237\u8868 expiration \u6539\u6210\u5230\u671f\u65f6\u95f4 \u540e\u7eed query                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : Vegetable <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u4e0d\u662f\uff0c\u4e0d\u8bf4 orm\uff0c\u4f60\u8fd9\u4e2a\u67e5\u8be2\u6211\u7528 sql \u4e5f\u4e0d\u4f1a\u5199\uff0c\u5199\u51fa\u6765\u4e5f\u4e0d\u77e5\u9053\u80fd\u4e0d\u80fd\u8d70\u7d22\u5f15\uff0c\u4e5f\u4e0d\u77e5\u9053\u4f1a\u4e0d\u4f1a\u6bcf\u884c\u90fd\u8ba1\u7b97\u4e00\u4e2a now                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : ytymf <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u6362\u4e2a\u601d\u8def\u5427\uff0c\u4e0d\u8ffd\u6c42\u5728\u6570\u636e\u5e93\u4e00\u6b21\u6027\u8fd4\u56de\u597d\uff0c\u628a\u5224\u65ad\u8fc7\u671f\u653e\u5728\u6570\u636e\u5e93\u5916\u505a\uff0c\u6548\u7387\u5e94\u8be5\u4e0d\u4f1a\u5dee\u7279\u522b\u591a, \u5185\u5b58\u5f97\u6ce8\u610f\u3002\u4e0d\u77e5\u9053\u6570\u636e\u5e93\u8868\u6709\u591a\u5927\u5462\uff1f
    \u4f2a\u4ee3\u7801\uff0c\u80e1\u5199\u7684\u3002
    resultList= []
    for each in InfoModel.objects.all():
     if datetime.now()-each.expiration < each.create_date:
     resultList.append()                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : ytymf <\/span>  <\/div>\n
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                                                                 resultList.append(each)\uff0c\u5199\u9519\u4e86                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : lonelinsky <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 1. data migration
    2. raw SQL<\/p>\n
    \ud83d\ude42                                                            <\/p><\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : izoabr <\/span>  <\/div>\n
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                                                                 \u4f60\u5e72\u8106\u52a0\u4e00\u4e2a model\uff0c\u4e24\u4e2a\u5b57\u6bb5\uff0c\u7b2c\u4e00\u4e2a\u5b57\u6bb5\u5173\u8054 InfoModel\uff0c\u7b2c\u4e8c\u4e2a\u5b57\u6bb5\u5230\u671f\u65f6\u95f4\u3002
    \u7b2c\u4e00\u4e2a\u5b57\u6bb5\u505a\u4e3b\u952e\uff0c\u7b2c\u4e8c\u4e2a\u5b57\u6bb5\u81ea\u52a8\u751f\u6210\uff0c\u53ef\u4ee5\u76f4\u63a5\u5199\u5230 class \u91cc\u3002
    \u7136\u540e Super \u4e00\u4e0b InfoModel \u7684 create \u65b9\u6cd5\uff0c\u987a\u8def\u53bb\u521b\u5efa\u4e00\u4e2a\u4f60\u7684\u65b0 model \u8bb0\u5f55\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : daya <\/span>  <\/div>\n
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                                                                 \u8ba1\u7b97\u51fa\u5f53\u524d\u65e5\u671f\u8ddf\u521b\u5efa\u65e5\u671f\u76f8\u5dee\u591a\u5c11\u5929\uff0c\u7136\u540e\u8ddf\u6709\u6548\u671f\u5b58\u7684\u5929\u6570\u6bd4\u8f83\u5927\u5c0f\u4e0d\u884c\u5417                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : bogun <\/span>  <\/div>\n
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                                                                 \u5b58\u6210\u65e5\u671f\u683c\u5f0f\uff0c\u5efa\u8868\u52a0\u4e0a\u7d22\u5f15\u3002\u53ef\u4ee5\u53c2\u8003 django session \u7684\u8fc7\u671f\u673a\u5236\u5b9e\u73b0                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : Jammar <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u5199\u4e2a\u811a\u672c,\u8ba1\u7b97\u4e00\u4e0b\u5269\u4f59\u65e5\u671f\u91cd\u65b0\u5efa\u8bae\u4e00\u4e2a\u8868,\u8fd9\u4e2a\u5c31\u5220\u4e86\u5427                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : oaix <\/span>  <\/div>\n
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                                                                 \u5728 sql \u5c42\uff0c\u53ef\u4ee5\u4f7f\u7528 generated column\uff0c\u6709\u4e2a\u660e\u663e\u7684\u4f18\u52bf\u5c31\u662f\u53ef\u4ee5\u5728\u5b83\u4e0a\u9762\u5efa\u7d22\u5f15\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : wd <\/span>  <\/div>\n
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                                                                 \u4f60\u52a0\u4e00\u4e2a\u81ea\u5b9a\u4e49\u7684\u8ba1\u7b97\u5b57\u6bb5\uff0c\u7136\u540e\u6839\u636e\u90a3\u4e24\u4e2a\u5b57\u6bb5\u4ea7\u751f\uff1f\u53e6\u5916\uff0c\u5982\u679c\u5df2\u7ecf\u77e5\u9053\u539f\u6765\u8bbe\u8ba1\u4e0d\u5408\u7406\u5c31\u60f3\u60f3\u600e\u4e48\u6539\u5427\uff0c\u7ee7\u7eed\u5f80\u5c4e\u5806\u62c9\u5c4e\u53ea\u80fd\u8ba9\u4ed6\u53d8\u5f97\u66f4\u96be\u6e05\u7406\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n","protected":false},"excerpt":{"rendered":"
    \u8bf7\u6559\u4e00\u4e2a Django ORM \u4e2d…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/100295"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=100295"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/100295\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=100295"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=100295"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=100295"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}