{"id":285,"date":"2025-04-01T19:02:18","date_gmt":"2025-04-01T11:02:18","guid":{"rendered":"https:\/\/www.meng-xun.top\/?p=285"},"modified":"2025-04-02T02:23:19","modified_gmt":"2025-04-01T18:23:19","slug":"%e3%80%90%e8%b5%84%e6%96%99%e3%80%91%e7%ac%ac%e4%ba%8c%e6%ac%a1%e6%95%b0%e6%8d%ae%e5%ba%93%e5%ae%9e%e9%aa%8c","status":"publish","type":"post","link":"https:\/\/www.meng-xun.top\/index.php\/2025\/04\/01\/%e3%80%90%e8%b5%84%e6%96%99%e3%80%91%e7%ac%ac%e4%ba%8c%e6%ac%a1%e6%95%b0%e6%8d%ae%e5%ba%93%e5%ae%9e%e9%aa%8c\/","title":{"rendered":"\u3010\u8d44\u6599\u3011\u7b2c\u4e8c\u6b21\u6570\u636e\u5e93\u5b9e\u9a8c\u62a5\u544a\uff08\u4fe1\u606f\u5b89\u5168\uff09"},"content":{"rendered":"<p><!-- wp:heading {\"level\":1,\"className\":\"md-end-block md-heading md-focus\"} --><\/p>\n<h1 class=\"wp-block-heading md-end-block md-heading md-focus\"><span class=\"md-plain md-expand\">\u6570\u636e\u5e93\u5b9e\u9a8c\u4f5c\u4e1a\u53ca\u8be6\u89e3<\/span><\/h1>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph --><\/p>\n<p>\u672c\u7ad9<span style=\"color: #ff0000;\">\u4ec5\u9650<\/span>\u4e2a\u4eba\u5b66\u4e60\u548c\u5206\u4eab\u7b14\u8bb0\u4f7f\u7528\uff0c\u8f6c\u8f7d\u8bf7\u6ce8\u660e\u51fa\u5904\u3002<\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u672c\u6b21\u6570\u636e\u5e93\u5b9e\u9a8c\u56f4\u7ed5\u5b66\u751f\u4fe1\u606f\u4e0e\u8bfe\u7a0b\u9009\u4fee\u7b49\u6570\u636e\u5c55\u5f00\uff0c\u65e8\u5728\u8003\u5bdf SQL \u8bed\u53e5\u7684\u4f7f\u7528\u4e0e\u6570\u636e\u67e5\u8be2\u903b\u8f91\u3002\u4e0b\u9762\u5bf9\u6bcf\u4e2a\u5b9e\u9a8c\u4efb\u52a1\u53ca\u5176\u5bf9\u5e94\u7684 SQL \u4ee3\u7801\u8fdb\u884c\u8be6\u7ec6\u4ecb\u7ecd\u3002<\/span><\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading md-focus\"} --><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading md-focus\"><span class=\"md-plain\">1. \u67e5\u8be2\u6240\u6709\u5b66\u751f\u7684\u4fe1\u606f<\/span><\/h3>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u8f93\u51fa\u6570\u636e\u5e93\u4e2d\u5b58\u50a8\u7684\u5168\u90e8\u5b66\u751f\u8bb0\u5f55\uff0c\u4ee5\u83b7\u53d6\u5b66\u751f\u8868\u7684\u5b8c\u6574\u4fe1\u606f\u3002<\/span><\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-heading\"} --><\/p>\n<p class=\"md-end-block md-heading\">\u00a0<\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:shortcode --><\/p>\n<pre class=\"prettyprint linenums\"><span class=\"cm-keyword\">SELECT<\/span> \\<span class=\"cm-operator\">*<\/span> <span class=\"cm-keyword\">FROM<\/span> students;<\/pre>\n<p><!-- \/wp:shortcode --><\/p>\n<p><!-- wp:paragraph --><\/p>\n<p>&nbsp;<\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT *<\/code><\/span><span class=\"md-plain\"> \u8868\u793a\u9009\u62e9\u8868\u4e2d\u7684\u6240\u6709\u5217\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM students<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u4ece <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>students<\/code><\/span><span class=\"md-plain\"> \u8868\u4e2d\u8fdb\u884c\u67e5\u8be2\u3002<\/span><\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">2. \u67e5\u8be2\u5b66\u53f7\u4e3a \u201c20100306\u201d \u7684\u5b66\u751f\u59d3\u540d\u548c\u5b66\u9662<\/span><\/h3>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u4ece\u5b66\u751f\u8868\u4e2d\u7b5b\u9009\u51fa\u5b66\u53f7\u4e3a \u201c20100306\u201d \u7684\u5b66\u751f\uff0c\u5e76\u83b7\u53d6\u5176\u59d3\u540d\u548c\u6240\u5c5e\u5b66\u9662\u4fe1\u606f\u3002<\/span><\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/p>\n<p class=\"md-end-block md-p\">\u00a0<\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:shortcode --><\/p>\n<pre class=\"prettyprint linenums\"><span role=\"presentation\"><span class=\"cm-keyword\">SELECT<\/span> name<span class=\"cm-punctuation\">,<\/span> college <span class=\"cm-keyword\">FROM<\/span> students <span class=\"cm-keyword\">WHERE<\/span> student\\_id <span class=\"cm-operator\">=<\/span> <span class=\"cm-string\">&#8216;20100306&#8217;<\/span><span class=\"cm-punctuation\">;<\/span><\/span><\/pre>\n<p><!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT name, college<\/code><\/span><span class=\"md-plain\"> \u9009\u62e9 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>name<\/code><\/span><span class=\"md-plain\"> \u548c <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>college<\/code><\/span><span class=\"md-plain\"> \u5217\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM students<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u67e5\u8be2\u8868\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>WHERE student_id = '20100306'<\/code><\/span><span class=\"md-plain\"> \u7528\u4e8e\u7b5b\u9009\u51fa\u5b66\u53f7\u4e3a \u201c20100306\u201d \u7684\u8bb0\u5f55\u3002<\/span><\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">3. \u67e5\u8be2\u6bcf\u4e2a\u5b66\u9662\u7684\u5b66\u751f\u6570<\/span><\/h3>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u7edf\u8ba1\u6bcf\u4e2a\u5b66\u9662\u7684\u5b66\u751f\u6570\u91cf\uff0c\u4e86\u89e3\u5404\u5b66\u9662\u7684\u5b66\u751f\u5206\u5e03\u60c5\u51b5\u3002<\/span><\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --><\/p>\n<p><pre class=\"prettyprint linenums\">SELECT college<span class=\"cm-punctuation\">,<\/span> <span class=\"cm-keyword\">COUNT<\/span><span class=\"cm-bracket\">(<\/span>\\<span class=\"cm-operator\">*<\/span><span class=\"cm-bracket\">)<\/span> <span class=\"cm-keyword\">AS<\/span> student\\_count <span role=\"presentation\"><span class=\"cm-keyword\">FROM<\/span> students<\/span> <span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\">GROUP<\/span> <span class=\"cm-keyword\">BY<\/span> college<span class=\"cm-punctuation\">;<\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT college, COUNT(*)<\/code><\/span><span class=\"md-plain\"> \u9009\u62e9 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>college<\/code><\/span><span class=\"md-plain\"> \u5217\u5e76\u7edf\u8ba1\u8bb0\u5f55\u6570\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>AS student_count<\/code><\/span><span class=\"md-plain\"> \u4e3a\u7edf\u8ba1\u7ed3\u679c\u547d\u540d\u3002<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM students<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u67e5\u8be2\u8868\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>GROUP BY college<\/code><\/span><span class=\"md-plain\"> \u6309\u5b66\u9662\u5bf9\u6570\u636e\u8fdb\u884c\u5206\u7ec4\uff0c\u786e\u4fdd\u6bcf\u4e2a\u5b66\u9662\u7684\u5b66\u751f\u6570\u88ab\u6b63\u786e\u7edf\u8ba1\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">4. \u67e5\u8be2 \u201c\u8ba1\u7b97\u673a\u5b66\u9662\u201d \u548c \u201c\u8f6f\u4ef6\u5b66\u9662\u201d \u7684\u5b66\u751f\u4fe1\u606f<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u83b7\u53d6 \u201c\u8ba1\u7b97\u673a\u5b66\u9662\u201d \u548c \u201c\u8f6f\u4ef6\u5b66\u9662\u201d \u7684\u5b66\u751f\u8be6\u7ec6\u4fe1\u606f\uff0c\u4ee5\u4fbf\u5206\u6790\u7279\u5b9a\u5b66\u9662\u7684\u5b66\u751f\u60c5\u51b5\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-punctuation\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span>SELECT<\/span> \\<span class=\"cm-operator\">*<\/span> <span class=\"cm-keyword\">FROM<\/span> students <span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\">WHERE<\/span> college <span class=\"cm-keyword\">IN<\/span> <span class=\"cm-bracket\">(<\/span><span class=\"cm-string\">&#8216;\u8ba1\u7b97\u673a\u5b66\u9662&#8217;<\/span><span class=\"cm-punctuation\">,<\/span> <span class=\"cm-string\">&#8216;\u8f6f\u4ef6\u5b66\u9662&#8217;<\/span><span class=\"cm-bracket\">)<\/span><span class=\"cm-punctuation\">;<span class=\"cm-keyword\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT *<\/code><\/span><span class=\"md-plain\"> \u9009\u62e9\u6240\u6709\u5217\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM students<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u67e5\u8be2\u8868\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>WHERE college IN ('\u8ba1\u7b97\u673a\u5b66\u9662', '\u8f6f\u4ef6\u5b66\u9662')<\/code><\/span><span class=\"md-plain\"> \u7b5b\u9009\u51fa\u5b66\u9662\u4e3a \u201c\u8ba1\u7b97\u673a\u5b66\u9662\u201d \u6216 \u201c\u8f6f\u4ef6\u5b66\u9662\u201d \u7684\u8bb0\u5f55\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">5. \u67e5\u8be2\u59d3\u540d\u4e2d\u542b\u6709 \u201c\u674e\u201d \u7684\u5b66\u751f<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u5728\u5b66\u751f\u8868\u4e2d\u67e5\u627e\u59d3\u540d\u5305\u542b \u201c\u674e\u201d \u5b57\u7684\u5b66\u751f\uff0c\u5b9e\u73b0\u6a21\u7cca\u67e5\u8be2\u529f\u80fd\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span>SELECT<\/span> \\<span class=\"cm-operator\">*<\/span> <span class=\"cm-keyword\">FROM<\/span> students<\/span> <span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\">WHERE<\/span> name <span class=\"cm-keyword\">LIKE<\/span> <span class=\"cm-string\">&#8216;%\u674e%&#8217;<\/span><span class=\"cm-punctuation\">;<span class=\"cm-keyword\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT *<\/code><\/span><span class=\"md-plain\"> \u9009\u62e9\u6240\u6709\u5217\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM students<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u67e5\u8be2\u8868\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>WHERE name LIKE '%\u674e%'<\/code><\/span><span class=\"md-plain\"> \u4f7f\u7528 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>LIKE<\/code><\/span><span class=\"md-plain\"> \u64cd\u4f5c\u7b26\u548c\u901a\u914d\u7b26 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>%<\/code><\/span><span class=\"md-plain\">\uff0c\u5339\u914d\u59d3\u540d\u4e2d\u4efb\u610f\u4f4d\u7f6e\u5305\u542b \u201c\u674e\u201d \u5b57\u7684\u8bb0\u5f55\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">6. \u67e5\u8be2\u5b66\u751f\u8868\u4e2d\u5e74\u9f84\u662f 18 \u548c 20 \u7684\u7537\u751f\u7684\u4fe1\u606f<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u7b5b\u9009\u51fa\u5e74\u9f84\u4e3a 18 \u5c81\u548c 20 \u5c81\u7684\u7537\u751f\u8bb0\u5f55\uff0c\u7528\u4e8e\u7279\u5b9a\u4eba\u7fa4\u7684\u6570\u636e\u63d0\u53d6\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span>SELECT<\/span> \\<span class=\"cm-operator\">*<\/span> <span class=\"cm-keyword\">FROM<\/span> students<\/span> <span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\">WHERE<\/span> age <span class=\"cm-keyword\">IN<\/span> <span class=\"cm-bracket\">(<\/span><span class=\"cm-number\">18<\/span><span class=\"cm-punctuation\">,<\/span> <span class=\"cm-number\">20<\/span><span class=\"cm-bracket\">)<\/span> <span class=\"cm-keyword\">AND<\/span> gender <span class=\"cm-operator\">=<\/span> <span class=\"cm-string\">&#8216;\u7537&#8217;<\/span><span class=\"cm-punctuation\">;<span class=\"cm-keyword\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT *<\/code><\/span><span class=\"md-plain\"> \u9009\u62e9\u6240\u6709\u5217\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM students<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u67e5\u8be2\u8868\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>WHERE age IN (18, 20) AND gender = '\u7537'<\/code><\/span><span class=\"md-plain\"> \u4f7f\u7528 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>IN<\/code><\/span><span class=\"md-plain\"> \u64cd\u4f5c\u7b26\u7b5b\u9009\u5e74\u9f84\u4e3a 18 \u6216 20 \u7684\u8bb0\u5f55\uff0c\u5e76\u901a\u8fc7 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>AND<\/code><\/span><span class=\"md-plain\"> \u8fde\u63a5\u6027\u522b\u4e3a \u201c\u7537\u201d \u7684\u6761\u4ef6\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">7. \u67e5\u8be2\u6bcf\u4e00\u95e8\u8bfe\u7a0b\u95f4\u63a5\u5148\u884c\u8bfe\u7684\u4fe1\u606f\uff08\u9664\u4e86\u81ea\u8fde\u63a5\uff0c\u8fd8\u6709\u5176\u4ed6\u65b9\u6cd5\u5417\uff1f\uff09<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u83b7\u53d6\u6bcf\u4e00\u95e8\u8bfe\u7a0b\u7684\u95f4\u63a5\u5148\u884c\u8bfe\u7a0b\u4fe1\u606f\uff0c\u63a2\u7d22\u9664\u81ea\u8fde\u63a5\u5916\u7684\u5b9e\u73b0\u65b9\u6cd5\uff0c\u6df1\u5165\u7406\u89e3\u6570\u636e\u4e4b\u95f4\u7684\u5c42\u7ea7\u5173\u7cfb\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span>WITH<\/span> RECURSIVE CoursePrecedence <span class=\"cm-keyword\">AS<\/span> <span class=\"cm-bracket\">(<\/span><\/span> <span role=\"presentation\"> <span class=\"cm-keyword\">SELECT<\/span> course\\_id<span class=\"cm-punctuation\">,<\/span> preceding\\_course\\_id<\/span> <span role=\"presentation\"> <span class=\"cm-keyword\">FROM<\/span> courses<\/span> <span role=\"presentation\"> <span class=\"cm-keyword\">WHERE<\/span> preceding\\_course\\_id <span class=\"cm-keyword\">IS<\/span> <span class=\"cm-keyword\">NOT<\/span> <span class=\"cm-atom\">NULL<\/span><\/span> <span role=\"presentation\"> <span class=\"cm-keyword\">UNION<\/span> <span class=\"cm-keyword\">ALL<\/span><\/span> <span role=\"presentation\"> <span class=\"cm-keyword\">SELECT<\/span> cp<span class=\"cm-variable-2\">.course<\/span>\\_id<span class=\"cm-punctuation\">,<\/span> c<span class=\"cm-variable-2\">.preceding<\/span>\\_course\\_id<\/span> <span role=\"presentation\"> <span class=\"cm-keyword\">FROM<\/span> CoursePrecedence cp<\/span> <span role=\"presentation\"> <span class=\"cm-keyword\">JOIN<\/span> courses c <span class=\"cm-keyword\">ON<\/span> cp<span class=\"cm-variable-2\">.preceding<\/span>\\_course\\_id <span class=\"cm-operator\">=<\/span> c<span class=\"cm-variable-2\">.course<\/span>\\_id<\/span> <span role=\"presentation\"> <span class=\"cm-keyword\">WHERE<\/span> c<span class=\"cm-variable-2\">.preceding<\/span>\\_course\\_id <span class=\"cm-keyword\">IS<\/span> <span class=\"cm-keyword\">NOT<\/span> <span class=\"cm-atom\">NULL<\/span><\/span> <span role=\"presentation\"><span class=\"cm-bracket\">)<\/span><\/span> <span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\">SELECT<\/span> \\<span class=\"cm-operator\">*<\/span> <span class=\"cm-keyword\">FROM<\/span> CoursePrecedence<span class=\"cm-punctuation\">;<span class=\"cm-keyword\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u4f7f\u7528\u9012\u5f52 CTE\uff08Common Table Expression\uff09\u5b9e\u73b0\u3002\u9996\u5148\uff0c\u521d\u59cb\u67e5\u8be2\u9009\u62e9\u6709\u5148\u884c\u8bfe\u7a0b\u7684\u8bb0\u5f55\u3002\u7136\u540e\uff0c\u901a\u8fc7\u9012\u5f52\u90e8\u5206\u4e0d\u65ad\u5339\u914d\u5148\u884c\u8bfe\u7a0b\uff0c\u83b7\u53d6\u95f4\u63a5\u5148\u884c\u8bfe\u7a0b\u4fe1\u606f\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">8. \u67e5\u8be2\u548c \u201c\u738b\u519b\u201d \u5728\u540c\u4e00\u4e2a\u5b66\u9662\u5b66\u4e60\u7684\u5b66\u751f\u4fe1\u606f<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u627e\u51fa\u4e0e \u201c\u738b\u519b\u201d \u5728\u540c\u4e00\u5b66\u9662\u7684\u5176\u4ed6\u5b66\u751f\u4fe1\u606f\uff0c\u5b9e\u73b0\u5173\u8054\u6570\u636e\u7684\u67e5\u8be2\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span>SELECT<\/span> s.\\<span class=\"cm-operator\">*<\/span><\/span> <span role=\"presentation\"><span class=\"cm-keyword\">FROM<\/span> students s<\/span> <span role=\"presentation\"><span class=\"cm-keyword\">JOIN<\/span> <span class=\"cm-bracket\">(<\/span><span class=\"cm-keyword\">SELECT<\/span> college <span class=\"cm-keyword\">FROM<\/span> students <span class=\"cm-keyword\">WHERE<\/span> name <span class=\"cm-operator\">=<\/span> <span class=\"cm-string\">&#8216;\u738b\u519b&#8217;<\/span><span class=\"cm-bracket\">)<\/span> t<\/span> <span role=\"presentation\"><span class=\"cm-keyword\">ON<\/span> s<span class=\"cm-variable-2\">.college<\/span> <span class=\"cm-operator\">=<\/span> t<span class=\"cm-variable-2\">.college<\/span><\/span> <span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\">WHERE<\/span> s<span class=\"cm-variable-2\">.name<\/span> <span class=\"cm-operator\">!=<\/span> <span class=\"cm-string\">&#8216;\u738b\u519b&#8217;<\/span><span class=\"cm-punctuation\">;<span class=\"cm-keyword\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u5b50\u67e5\u8be2 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT college FROM students WHERE name = '\u738b\u519b'<\/code><\/span><span class=\"md-plain\"> \u83b7\u53d6 \u201c\u738b\u519b\u201d \u7684\u5b66\u9662\u3002\u4e3b\u67e5\u8be2\u901a\u8fc7 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>JOIN<\/code><\/span><span class=\"md-plain\"> \u5c06\u5b66\u751f\u8868\u4e0e\u5b50\u67e5\u8be2\u7ed3\u679c\u8fde\u63a5\uff0c\u7b5b\u9009\u51fa\u540c\u5b66\u9662\u4e14\u59d3\u540d\u4e0d\u4e3a \u201c\u738b\u519b\u201d \u7684\u5b66\u751f\u8bb0\u5f55\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">9. \u67e5\u8be2\u6bcf\u4e2a\u5b66\u751f\u9009\u4fee\u7684\u8bfe\u7a0b\u6570<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u7edf\u8ba1\u6bcf\u4e2a\u5b66\u751f\u9009\u4fee\u7684\u8bfe\u7a0b\u6570\u91cf\uff0c\u4e86\u89e3\u5b66\u751f\u7684\u9009\u8bfe\u60c5\u51b5\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-punctuation\"><span class=\"cm-keyword\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span><\/span><\/span>SELECT student\\_id, COUNT(course\\_id) AS course\\_count FROM enrollments GROUP BY student\\_id;<span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT student_id, COUNT(course_id)<\/code><\/span><span class=\"md-plain\"> \u9009\u62e9\u5b66\u751f ID \u5e76\u7edf\u8ba1\u8bfe\u7a0b\u6570\u91cf\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>AS course_count<\/code><\/span><span class=\"md-plain\"> \u4e3a\u7edf\u8ba1\u7ed3\u679c\u547d\u540d\u3002<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM enrollments<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u67e5\u8be2\u8868\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>GROUP BY student_id<\/code><\/span><span class=\"md-plain\"> \u6309\u5b66\u751f ID \u8fdb\u884c\u5206\u7ec4\uff0c\u786e\u4fdd\u6bcf\u4e2a\u5b66\u751f\u7684\u9009\u8bfe\u6570\u88ab\u6b63\u786e\u7edf\u8ba1\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">10. \u67e5\u8be2\u5b66\u751f\u7684\u6210\u7ee9\uff0c\u6309\u7167\u5b66\u53f7\u7684\u5347\u5e8f\uff0c\u6210\u7ee9\u7684\u964d\u5e8f\u7684\u65b9\u5f0f\u663e\u793a<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u4ee5\u5b66\u53f7\u5347\u5e8f\u3001\u6210\u7ee9\u964d\u5e8f\u7684\u987a\u5e8f\u5c55\u793a\u5b66\u751f\u6210\u7ee9\uff0c\u65b9\u4fbf\u5bf9\u6210\u7ee9\u6570\u636e\u8fdb\u884c\u6392\u5e8f\u67e5\u770b\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span><\/span><\/span>SELECT student\\_id, course\\_id, grade FROM enrollments ORDER BY student\\_id ASC, grade DESC;<span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT student_id, course_id, grade<\/code><\/span><span class=\"md-plain\"> \u9009\u62e9\u76f8\u5173\u5217\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM enrollments<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u67e5\u8be2\u8868\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>ORDER BY student_id ASC, grade DESC<\/code><\/span><span class=\"md-plain\"> \u4f7f\u7528 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>ORDER BY<\/code><\/span><span class=\"md-plain\"> \u5bf9\u7ed3\u679c\u8fdb\u884c\u6392\u5e8f\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>ASC<\/code><\/span><span class=\"md-plain\"> \u8868\u793a\u5347\u5e8f\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>DESC<\/code><\/span><span class=\"md-plain\"> \u8868\u793a\u964d\u5e8f\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">11. \u67e5\u8be2\u5b66\u751f\u5927\u4e8e\u5176\u9009\u4fee\u8bfe\u7a0b\u5e73\u5747\u6210\u7ee9\u7684\u9009\u8bfe\u4fe1\u606f<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u627e\u51fa\u5b66\u751f\u6210\u7ee9\u9ad8\u4e8e\u5176\u9009\u4fee\u8bfe\u7a0b\u5e73\u5747\u6210\u7ee9\u7684\u9009\u8bfe\u8bb0\u5f55\uff0c\u7528\u4e8e\u5206\u6790\u5b66\u751f\u7684\u76f8\u5bf9\u6210\u7ee9\u8868\u73b0\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-fences mock-cm md-end-block\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-fences mock-cm md-end-block\">\u00a0<\/p>\n<p><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span><\/span><\/span>SELECT e.\\* FROM enrollments e JOIN ( SELECT student\\_id, AVG(grade) AS avg\\_grade FROM enrollments GROUP BY student\\_id ) t ON e.student\\_id = t.student\\_id WHERE e.grade &gt; t.avg\\_grade;<span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:paragraph --><\/span><\/span><\/span><\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u5b50\u67e5\u8be2 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT student_id, AVG(grade) AS avg_grade FROM enrollments GROUP BY student_id<\/code><\/span><span class=\"md-plain\"> \u8ba1\u7b97\u6bcf\u4e2a\u5b66\u751f\u7684\u5e73\u5747\u6210\u7ee9\u3002\u4e3b\u67e5\u8be2\u901a\u8fc7 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>JOIN<\/code><\/span><span class=\"md-plain\"> \u5c06\u9009\u8bfe\u8868\u4e0e\u5b50\u67e5\u8be2\u7ed3\u679c\u8fde\u63a5\uff0c\u7b5b\u9009\u51fa\u6210\u7ee9\u9ad8\u4e8e\u5e73\u5747\u6210\u7ee9\u7684\u8bb0\u5f55\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">12. \u67e5\u8be2\u6210\u7ee9\u5728 80<\/span>~<span class=\"md-plain\">89\uff08\u5305\u542b 80 \u548c 89\uff09\u7684\u5b66\u751f\u7684\u59d3\u540d\uff0c\u8bfe\u7a0b\u540d\u79f0\u548c\u6210\u7ee9<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u83b7\u53d6\u6210\u7ee9\u5728 80 \u5230 89 \u5206\u4e4b\u95f4\u7684\u5b66\u751f\u7684\u76f8\u5173\u4fe1\u606f\uff0c\u7528\u4e8e\u7279\u5b9a\u5206\u6570\u6bb5\u5b66\u751f\u6570\u636e\u7684\u5206\u6790\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span><\/span><\/span>SELECT s.name, c.course\\_name, e.grade FROM students s JOIN enrollments e ON s.student\\_id = e.student\\_id JOIN courses c ON e.course\\_id = c.course\\_id WHERE e.grade BETWEEN 80 AND 89;<span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u901a\u8fc7 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>JOIN<\/code><\/span><span class=\"md-plain\"> \u64cd\u4f5c\u5c06\u5b66\u751f\u8868\u3001\u9009\u8bfe\u8868\u548c\u8bfe\u7a0b\u8868\u8fde\u63a5\u8d77\u6765\uff0c\u83b7\u53d6\u5b66\u751f\u59d3\u540d\u3001\u8bfe\u7a0b\u540d\u79f0\u548c\u6210\u7ee9\u3002<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>WHERE e.grade BETWEEN 80 AND 89<\/code><\/span><span class=\"md-plain\"> \u7b5b\u9009\u51fa\u6210\u7ee9\u5728 80 \u5230 89 \u5206\u4e4b\u95f4\u7684\u8bb0\u5f55\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">13. \u67e5\u8be2\u9009\u4fee\u4e86 \u201c0001\u201d \u8bfe\u7a0b\u7684\u5b66\u751f\u59d3\u540d<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u627e\u51fa\u9009\u4fee\u4e86 \u201c0001\u201d \u8bfe\u7a0b\u7684\u5b66\u751f\u59d3\u540d\uff0c\u7528\u4e8e\u7279\u5b9a\u8bfe\u7a0b\u9009\u8bfe\u5b66\u751f\u7684\u4fe1\u606f\u83b7\u53d6\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span><\/span><\/span>SELECT s.name FROM students s JOIN enrollments e ON s.student\\_id = e.student\\_id WHERE e.course\\_id = &#8216;0001&#8217;;<span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u901a\u8fc7 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>JOIN<\/code><\/span><span class=\"md-plain\"> \u5c06\u5b66\u751f\u8868\u548c\u9009\u8bfe\u8868\u8fde\u63a5\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>WHERE e.course_id = '0001'<\/code><\/span><span class=\"md-plain\"> \u7b5b\u9009\u51fa\u9009\u4fee \u201c0001\u201d \u8bfe\u7a0b\u7684\u8bb0\u5f55\uff0c\u83b7\u53d6\u5bf9\u5e94\u7684\u5b66\u751f\u59d3\u540d\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">14. \u67e5\u8be2\u81f3\u5c11\u9009\u4fee\u4e86 \u201c20100101\u201d \u5b66\u751f\u9009\u4fee\u7684\u5168\u90e8\u8bfe\u7a0b\u7684\u5b66\u751f\u5b66\u53f7\u548c\u59d3\u540d<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u627e\u51fa\u81f3\u5c11\u9009\u4fee\u4e86 \u201c20100101\u201d \u5b66\u751f\u6240\u9009\u5168\u90e8\u8bfe\u7a0b\u7684\u5b66\u751f\u4fe1\u606f\uff0c\u7528\u4e8e\u6bd4\u8f83\u5b66\u751f\u9009\u8bfe\u7684\u8986\u76d6\u60c5\u51b5\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span><\/span><\/span>SELECT s.student\\_id, s.name FROM students s JOIN enrollments e ON s.student\\_id = e.student\\_id GROUP BY s.student\\_id, s.name HAVING COUNT(DISTINCT e.course\\_id) &gt;= ( SELECT COUNT(DISTINCT course\\_id) FROM enrollments WHERE student\\_id = &#8216;20100101&#8217; ) AND NOT EXISTS ( SELECT course\\_id FROM enrollments WHERE student\\_id = &#8216;20100101&#8217; AND course\\_id NOT IN ( SELECT course\\_id FROM enrollments WHERE student\\_id = s.student\\_id ; ) );<span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>\u4ee3\u7801\u89e3\u91ca<\/code><\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u5b50\u67e5\u8be2\u8ba1\u7b97 \u201c20100101\u201d \u5b66\u751f\u9009\u4fee\u7684\u8bfe\u7a0b\u6570\uff0c\u5e76\u68c0\u67e5\u662f\u5426\u5b58\u5728\u8be5\u5b66\u751f\u9009\u4fee\u800c\u5176\u4ed6\u5b66\u751f\u672a\u9009\u4fee\u7684\u8bfe\u7a0b\u3002\u4e3b\u67e5\u8be2\u901a\u8fc7 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>GROUP BY<\/code><\/span><span class=\"md-plain\"> \u548c <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>HAVING<\/code><\/span><span class=\"md-plain\"> \u7b5b\u9009\u51fa\u6ee1\u8db3\u6761\u4ef6\u7684\u5b66\u751f\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:separator --><\/span><\/span><\/span><\/span><\/p>\n<hr class=\"wp-block-separator has-alpha-channel-opacity\" \/>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:separator --><\/p>\n<p><!-- wp:heading {\"level\":3,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h3 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">15. \u67e5\u8be2\u5b66\u53f7\u4e2d\u5012\u6570\u7b2c\u4e09\u4e2a\u5b57\u7b26\u662f \u201c1\u201d \u7684\u5b66\u751f\u4fe1\u606f<\/span><\/h3>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4efb\u52a1\u63cf\u8ff0<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p\"><span class=\"md-plain\">\u7b5b\u9009\u51fa\u5b66\u53f7\u4e2d\u5012\u6570\u7b2c\u4e09\u4e2a\u5b57\u7b26\u4e3a \u201c1\u201d \u7684\u5b66\u751f\u8bb0\u5f55\uff0c\u5b9e\u73b0\u7279\u5b9a\u683c\u5f0f\u5b66\u53f7\u7684\u67e5\u8be2\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">SQL \u4ee3\u7801<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:preformatted --><\/span><\/span><\/span><\/span><\/p>\n<pre class=\"wp-block-preformatted\">\u00a0<\/pre>\n<p><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:preformatted --><\/p>\n<p><!-- wp:shortcode --> <pre class=\"prettyprint linenums\"><\/span><\/span><\/span>SELECT \\* FROM students WHERE student\\_id LIKE &#8216;%\\_1\\_&#8217;;<span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><\/pre> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:heading {\"level\":4,\"className\":\"md-end-block md-heading\"} --><\/span><\/span><\/span><\/span><\/p>\n<h4 class=\"wp-block-heading md-end-block md-heading\"><span class=\"md-plain\">\u4ee3\u7801\u89e3\u91ca<\/span><\/h4>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:heading --><\/p>\n<p><!-- wp:paragraph {\"className\":\"md-end-block md-p md-focus\"} --><\/span><\/span><\/span><\/span><\/p>\n<p class=\"md-end-block md-p md-focus\"><span class=\"md-pair-s\" spellcheck=\"false\"><code>SELECT *<\/code><\/span><span class=\"md-plain\"> \u9009\u62e9\u6240\u6709\u5217\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>FROM students<\/code><\/span><span class=\"md-plain\"> \u6307\u5b9a\u67e5\u8be2\u8868\uff0c<\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>WHERE student_id LIKE '%_1_'<\/code><\/span><span class=\"md-plain\"> \u4f7f\u7528 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>LIKE<\/code><\/span><span class=\"md-plain\"> \u64cd\u4f5c\u7b26\u548c\u901a\u914d\u7b26 <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>%<\/code><\/span><span class=\"md-plain\"> \u548c <\/span><span class=\"md-pair-s\" spellcheck=\"false\"><code>_<\/code><\/span><span class=\"md-plain md-expand\">\uff0c\u5339\u914d\u5b66\u53f7\u4e2d\u5012\u6570\u7b2c\u4e09\u4e2a\u5b57\u7b26\u4e3a \u201c1\u201d \u7684\u8bb0\u5f55\u3002<\/span><\/p>\n<p><span role=\"presentation\"><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/p>\n<p><!-- wp:shortcode --> <h2 class=\"section-title\"><span><i class=\"fa fa-cloud-download\"><\/i>\u4e0b\u8f7dmd\u683c\u5f0f\u539f\u6587<\/span><\/h2> <!-- \/wp:shortcode --><\/p>\n<p><!-- wp:paragraph --><\/span><\/span><\/span><\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span role=\"presentation\"><span class=\"cm-keyword\"><span class=\"cm-punctuation\"><!-- \/wp:paragraph --><\/span><\/span><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6570\u636e\u5e93\u5b9e\u9a8c\u4f5c\u4e1a\u53ca\u8be6\u89e3 \u672c\u7ad9\u4ec5\u9650\u4e2a\u4eba\u5b66\u4e60\u548c\u5206\u4eab\u7b14\u8bb0\u4f7f\u7528\uff0c\u8f6c\u8f7d\u8bf7\u6ce8\u660e\u51fa\u5904\u3002 \u672c\u6b21\u6570\u636e\u5e93\u5b9e\u9a8c\u56f4\u7ed5\u5b66\u751f\u4fe1\u606f\u4e0e\u8bfe\u7a0b\u9009\u4fee\u7b49\u6570\u636e\u5c55\u5f00\uff0c\u65e8\u5728\u8003\u5bdf SQL \u8bed\u53e5\u7684\u4f7f\u7528\u4e0e\u6570\u636e\u67e5\u8be2\u903b\u8f91\u3002\u4e0b\u9762\u5bf9\u6bcf\u4e2a\u5b9e\u9a8c\u4efb\u52a1\u53ca\u5176\u5bf9\u5e94\u7684 SQL \u4ee3\u7801\u8fdb\u884c\u8be6\u7ec6\u4ecb\u7ecd\u3002 1. \u67e5\u8be2\u6240\u6709\u5b66\u751f\u7684\u4fe1\u606f \u4efb\u52a1\u63cf\u8ff0 \u8f93\u51fa\u6570\u636e\u5e93\u4e2d\u5b58\u50a8\u7684\u5168\u90e8\u5b66\u751f\u8bb0\u5f55\uff0c\u4ee5\u83b7\u53d6\u5b66\u751f\u8868\u7684\u5b8c\u6574\u4fe1\u606f\u3002 SQL \u4ee3\u7801 \u00a0 &nbsp; \u4ee3\u7801\u89e3\u91ca SELECT * \u8868\u793a\u9009\u62e9\u8868\u4e2d\u7684\u6240\u6709\u5217\uff0cF [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":312,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[18],"class_list":["post-285","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-6","tag-18"],"_links":{"self":[{"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/posts\/285","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/comments?post=285"}],"version-history":[{"count":27,"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/posts\/285\/revisions"}],"predecessor-version":[{"id":358,"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/posts\/285\/revisions\/358"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/media\/312"}],"wp:attachment":[{"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/media?parent=285"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/categories?post=285"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.meng-xun.top\/index.php\/wp-json\/wp\/v2\/tags?post=285"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}