1\u3001\t\u5bf9\u67e5\u8be2\u8fdb\u884c\u4f18\u5316\uff0c\u5e94\u5c3d\u91cf\u907f\u514d\u5168\u8868\u626b\u63cf\uff0c\u9996\u5148\u5e94\u8003\u8651\u5728where\u53caorder by\u6d89\u53ca\u7684\u5217\u4e0a\u5efa\u7acb\u7d22\u5f15\u3002
\n2\u3001\t\u5e94\u5c3d\u91cf\u907f\u514d\u5728where\u5b50\u53e5\u4e2d\u5bf9\u5b57\u6bb5\u8fdb\u884cnull\u503c\u5224\u65ad\uff0c\u5426\u5219\u5c06\u5bfc\u81f4\u5f15\u64ce\u653e\u5f03\u4f7f\u7528\u7d22\u5f15\u800c\u8fdb\u884c\u5168\u8868\u626b\u63cf\uff0c\u5982\uff1a
\nselect id from t where num is null
\n–\u53ef\u4ee5\u5728num\u4e0a\u8bbe\u7f6e\u9ed8\u8ba4\u503c0,\u786e\u4fdd\u8868\u4e2dnum\u5217\u6ca1\u6709null\u503c\uff0c\u7136\u540e\u8fd9\u6837\u67e5\u8be2\uff1a
\nselect id from t where num=0
\n3\u3001\t\u5e94\u5c3d\u91cf\u907f\u514d\u5728where\u5b50\u53e5\u4e2d\u4f7f\u7528!=\u6216<>\u64cd\u4f5c\u7b26\uff0c\u5426\u5219\u5f15\u64ce\u5c06\u653e\u5f03\u4f7f\u7528\u7d22\u5f15\u800c\u8fdb\u884c\u5168\u8868\u626b \u63cf\u3002
\n4\u3001\t\u5e94\u5c3d\u91cf\u907f\u514d\u5728where\u5b50\u53e5\u4e2d\u4f7f\u7528or\u6765\u8fde\u63a5\u6761\u4ef6\uff0c\u5426\u5219\u5c06\u5bfc\u81f4\u5f15\u64ce\u653e\u5f03\u4f7f\u7528\u7d22\u5f15\u800c\u8fdb\u884c \u5168\u8868\u626b\u63cf\uff0c\u5982\uff1a
\nselect id from t where num=10 or num=20
\n–\u53ef\u4ee5\u8fd9\u6837\u67e5\u8be2\uff1a
\nselect id from t where num=10 union all select id from t where num=20
\n5\u3001\tin\u548cnot in\u4e5f\u8981\u614e\u7528\uff0c\u5426\u5219\u4f1a\u5bfc\u81f4\u5168\u8868\u626b\u63cf\uff0c\u5982\uff1a
\nselect id from t where num in (1, 2, 3)
\n–\u5bf9\u4e8e\u8fde\u7eed\u7684\u6570\u503c\uff0c\u80fd\u7528between\u5c31\u4e0d\u8981\u7528in \u4e86:
\nselect id from t where num between 1 and 3
\n6\u3001\t\u4e0b\u9762\u7684\u67e5\u8be2\u4e5f\u5c06\u5bfc\u81f4\u5168\u8868\u626b\u63cf\uff1aselect id from t where name like ‘%\u674e\uff05’\u82e5\u8981\u63d0\u9ad8\u6548\u7387\uff0c\u53ef\u4ee5\u8003\u8651\u5168\u6587\u68c0\u7d22\u3002
\n7\u3001\t\u5982\u679c\u5728where\u5b50\u53e5\u4e2d\u4f7f\u7528\u53c2\u6570\uff0c\u4e5f\u4f1a\u5bfc\u81f4\u5168\u8868\u626b\u63cf\u3002\u56e0\u4e3aSQL\u53ea\u6709\u5728\u8fd0\u884c\u65f6\u624d\u4f1a\u89e3\u6790\u5c40\u90e8\u53d8\u91cf\uff0c\u4f46\u4f18\u5316\u7a0b\u5e8f\u4e0d\u80fd\u5c06\u8bbf\u95ee\u8ba1\u5212\u7684\u9009\u62e9\u63a8\u8fdf\u5230\u8fd0\u884c\u65f6\uff1b\u5b83\u5fc5\u987b\u5728\u7f16\u8bd1\u65f6\u8fdb\u884c\u9009\u62e9\u3002\u7136\u800c,\u5982\u679c\u5728\u7f16\u8bd1\u65f6\u5efa\u7acb\u8bbf\u95ee\u8ba1\u5212\uff0c\u53d8\u91cf\u7684\u503c\u8fd8\u662f\u672a\u77e5\u7684\uff0c\u56e0\u800c\u65e0\u6cd5\u4f5c\u4e3a\u7d22\u5f15\u9009\u62e9\u7684\u8f93\u5165\u9879\u3002\u5982\u4e0b\u9762\u8bed\u53e5\u5c06\u8fdb\u884c\u5168\u8868\u626b\u63cf\uff1a
\nselect id from t where num=@num
\n–\u53ef\u4ee5\u6539\u4e3a\u5f3a\u5236\u67e5\u8be2\u4f7f\u7528\u7d22\u5f15\uff1a
\nselect id from t with(index(\u7d22\u5f15\u540d))where num=@num
\n8\u3001\t\u5e94\u5c3d\u91cf\u907f\u514d\u5728where\u5b50\u53e5\u4e2d\u5bf9\u5b57\u6bb5\u8fdb\u884c\u8868\u8fbe\u5f0f\u64cd\u4f5c\uff0c\u8fd9\u5c06\u5bfc\u81f4\u5f15\u64ce\u653e\u5f03\u4f7f\u7528\u7d22\u5f15\u800c\u8fdb\u884c\u5168\u8868\u626b\u63cf\u3002\u5982\uff1a
\nselect id from t where num\/2=100
\n–\u5e94\u6539\u4e3a\uff1a
\nselect id from t where num=100*2
\n9\u3001\t\u5e94\u5c3d\u91cf\u907f\u514d\u5728where\u5b50\u53e5\u4e2d\u5bf9\u5b57\u6bb5\u8fdb\u884c\u51fd\u6570\u64cd\u4f5c\uff0c\u8fd9\u5c06\u5bfc\u81f4\u5f15\u64ce\u653e\u5f03\u4f7f\u7528\u7d22\u5f15\u800c\u8fdb\u884c\u5168\u8868\u626b\u63cf\u3002\u5982\uff1a
\nselect id from t where substring(name, 1, 3)=’ abc’
\n–name\u4ee5abc\u5f00\u5934\u7684id\u5e94\u6539\u4e3a\uff1a
\nselect id from t where name like ‘abc%’
\n10\u3001\u4e0d\u8981\u5728where\u5b50\u53e5\u4e2d\u7684"=\u201d\u5de6\u8fb9\u8fdb\u884c\u51fd\u6570\u3001\u7b97\u672f\u8fd0\u7b97\u6216\u5176\u4ed6\u8868\u8fbe\u5f0f\u8fd0\u7b97\uff0c\u5426\u5219\u7cfb\u7edf\u5c06\u53ef\u80fd\u65e0\u6cd5\u6b63\u786e\u4f7f\u7528\u7d22\u5f15\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
1\u3001 \u5bf9\u67e5\u8be2\u8fdb\u884c\u4f18\u5316\uff0c\u5e94\u5c3d\u91cf\u907f\u514d\u5168\u8868\u626b\u63cf\uff0c\u9996\u5148\u5e94\u8003\u8651\u5728where\u53caorder by\u6d89\u53ca\u7684\u5217\u4e0a\u5efa\u7acb\u7d22\u5f15\u3002 2\u3001 […]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[102],"tags":[],"class_list":["post-7848","post","type-post","status-publish","format-standard","hentry","category-db"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/7848","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=7848"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/7848\/revisions"}],"predecessor-version":[{"id":7849,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/7848\/revisions\/7849"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=7848"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=7848"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=7848"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}