\t\t\t\t\u5b57\u4e32 \u5e74\u6708 \u8f49 \u65e5\u671f\u683c\u5f0f \u5e74\u6708\u65e5\uff08 \u5b57\u4e32\u8f49\u65e5\u671f \uff09
\n\u6700\u8fd1\u5de5\u4f5c\u4e0a\u53c8\u9047\u5230\u4e86\u5947\u8469\u7684\u9700\u6c42\uff0c\u901a\u5e38\u6211\u5011\u5728\u9700\u6c42\u5206\u6790\u7684\u6642\u5019\u5c31\u6703\u78ba\u8a8d\u6b04\u4f4d\u7684\u683c\u5f0f\uff0c\u4ee5\u672c\u6848\u4f8b\u4f86\u8aaa \u56e0\u70ba\u6709\u5e74\u6708\u7684\u7d71\u8a08\u9700\u6c42\uff0c\u65e5\u671f\u683c\u5f0f\u53c8\u6c92\u6709\u5e74\u6708\uff1b\u6240\u4ee5\u5c0f\u7de8\u5728\u554f\u6e05\u695a\u4e0d\u6703\u7570\u52d5\u6b64\u6b04\u4f4d\u5f8c\uff0c\u81ea\u4ee5\u70ba\u8070\u660e\u7684\u4ee5\u5b57\u4e32\u65b9\u5f0f\u5132\u5b58\u5e74\u6708\u6b04\u4f4d\uff08’201811’\uff09\uff0c\u5c31\u5728\u7cfb\u7d71\u4e0a\u7dda\u5f8c\u7684\u5e7e\u500b\u6708\u5f8c\uff0c\u7a81\u7136\u8aaa\u8981\u6539\u6210\u5e74\u6708\u65e5\uff08\u7ffb\u684c\uff09\uff0c\u88e1\u9762\u5df2\u7d93\u6709\u4e0d\u5c11\u8cc7\u6599\u4e86\uff1b\u53c8\u4e0d\u53ef\u80fd\u91cd\u65b0\u8f38\u5165\uff0cvarchar => date \u662f\u6703\u88ab\u6e05\u7a7a\u8cc7\u6599\u8b8a 0000-00-00\uff0c\u4f46\u9019\u662f\u5687\u4e0d\u4e86\u6211\u7684
\n
\n\u6253\u6efe\u90a3\u9ebc\u591a\u5e74\u4ec0\u9ebc\u5996\u9b54\u9b3c\u602a\u6c92\u78b0\u904e\uff0c\u4ee5\u4e0b\u5206\u4eab\u6211\u7684\u89e3\u6cd5\uff1a
\n\u6709\u66f4\u597d\u7684\u89e3\u6cd5\u6b61\u8fce\u5206\u4eab\uff0c\u6709\u932f\u4e5f\u8acb\u591a\u591a\u6307\u6559
\n\u6015\u6b7b\u7684\u6211\u5148\u9a57\u8b49\u4e00\u4e0b\u9019\u4f5c\u6cd5\u53ef\u4e0d\u53ef\u884c
\n1.\u5148\u628a\u5e74\u6708\u5207\u5272\u986f\u793a\u51fa\u4f86
\nsql\u8a9e\u6cd5\uff1aSELECT *, SUBSTRING(`ym`,1,4) as y,SUBSTRING(`ym`,5,2) as m FROM `table` WHERE 1
\n2.\u518d\u7d44\u5408\u4e00\u4e0b\u5207\u5272\u51fa\u4f86\u7684\u5b57\u4e32\u8b93\u5b83\u8b8a\u6210\u5408\u6cd5\u7684\u65e5\u671f\u683c\u5f0f
\nsql\u8a9e\u6cd5\uff1aSELECT concat(SUBSTRING(`ym`,1,4),’-‘,SUBSTRING(`ym`,5,2),’-01′) as cc FROM `table` WHERE 1
\n3.\u5efa\u7acb\u65b0\u7684\u6b04\u4f4d `ymd`
\n4.\u5c07\u5b8c\u6574\u7684\u65e5\u671f\u683c\u5f0f\u5beb\u5165 `ymd`
\nsql\u8a9e\u6cd5\uff1aUPDATE `table` SET `ymd`=concat(SUBSTRING(`ym`,1,4),’-‘,SUBSTRING(`ym`,5,2),’-01′) WHERE 1
\n5.\u5c07 `ymd` \u7684\u8cc7\u6599\u5beb\u5165\u539f\u672c\u7684 `ym` \uff08\u5176\u5be6\u662f\u53ef\u4ee5\u76f4\u63a5\u7528 `ymd` \u4f46\u6211\u5831\u8868\u90fd\u5beb\u597d\u4e86\u4e0d\u60f3\u6539\u4e86\uff09
\nsql\u8a9e\u6cd5\uff1aUPDATE `table` SET `ym`=`ymd`
\n6.\u522a\u9664 `ymd` \u6b04\u4f4d
\n\u6253\u5b8c\u6536\u5de5\uff01\uff5e
\n\u7d93\u904e\u6b64\u6b21\u7d93\u9a57\uff0c\u4ee5\u5f8c\u6709\u5e74\u6708\u7684\u7d71\u8a08\u9700\u6c42 \u7d71\u4e00\u90fd\u8a2d\u70ba\u65e5\u671f\u683c\u5f0f\uff0c\u5c31\u7b97\u524d\u7aef\u53ea\u986f\u793a\u5e74\u6708\u5beb\u5165\u6642\u518d\u88dc 01 \u9019\u500b\u65e5\u671f\uff1b
\n\u514d\u5f97\u53c8\u88ab\u80cc\u5f8c\u6876\u4e00\u5200\u3002
\n\u88dc\u5145\uff1a\u4e0a\u9762\u6703\u7528\u5230\u5169\u500bmysql\u7684\u529f\u80fd\u51fd\u5f0f
\nSUBSTRING(`ym`,1,4) \u5206\u5272\u5b57\u4e32\uff08’\u8981\u5206\u5272\u7684\u5b57\u4e32 \u53ef\u4ee5\u7d14\u5b57\u4e32 \u6216 \u6b04\u4f4d\u540d\u7a31 \u6216 \u5b50\u67e5\u8a62’,\u5f9e\u90a3\u88e1\u958b\u59cb\u5206\u5272\uff0c\u8981\u5206\u5272\u7684\u9577\u5ea6\uff09\u3002
\nconcat(‘2019′,’-‘,’01’,’-01′) \u5b57\u4e32\u76f8\u52a0 (‘\u5b57\u4e321′,’\u5b57\u4e322’\uff0c’\u6b04\u4f4d\u540d\u7a31 \u6216 \u5b50\u67e5\u8a62’)\u3002\u6bcf\u500b\u5b57\u4e32\u4e2d\u9593\u5c31\u662f\u52a0\u9017\u865f\u5373\u53ef\u6574\u500b\u4e32\u6210\u4e00\u500b\u5b57\u4e32\u3002\t\t<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5b57\u4e32 \u5e74\u6708 \u8f49 \u65e5\u671f\u683c\u5f0f \u5e74\u6708\u65e5\uff08 \u5b57\u4e32\u8f49\u65e5\u671f \uff09…<\/p>\n","protected":false},"author":1,"featured_media":1867,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[34],"tags":[175,402,547,784,789,790,835,836],"class_list":["post-2737","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mysql","tag-concat","tag-mysql","tag-substring","tag-784","tag-789","tag-790","tag-835","tag-836","hvn-theme-has-thumbnail"],"_links":{"self":[{"href":"https:\/\/www.webteach.tw\/index.php?rest_route=\/wp\/v2\/posts\/2737","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.webteach.tw\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.webteach.tw\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.webteach.tw\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.webteach.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2737"}],"version-history":[{"count":0,"href":"https:\/\/www.webteach.tw\/index.php?rest_route=\/wp\/v2\/posts\/2737\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.webteach.tw\/index.php?rest_route=\/wp\/v2\/media\/1867"}],"wp:attachment":[{"href":"https:\/\/www.webteach.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2737"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.webteach.tw\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2737"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.webteach.tw\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2737"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}