{"id":220,"date":"2024-06-18T11:05:30","date_gmt":"2024-06-18T03:05:30","guid":{"rendered":"http:\/\/zhaoyanqi.cn\/?p=220"},"modified":"2024-06-18T11:06:31","modified_gmt":"2024-06-18T03:06:31","slug":"mysql%e8%a7%86%e5%9b%be","status":"publish","type":"post","link":"https:\/\/zhaoyanqi.cn\/?p=220","title":{"rendered":"mysql\u89c6\u56fe"},"content":{"rendered":"\n<h3 class=\"wp-block-heading\" id=\"8e63c8a8\">\u4e00 \u89c6\u56fe<\/h3>\n\n\n\n<p id=\"u42bca334\">\u89c6\u56fe\u662f\u4e00\u4e2a\u865a\u62df\u8868\uff08\u975e\u771f\u5b9e\u5b58\u5728\uff09\uff0c\u5176\u672c\u8d28\u662f\u3010\u6839\u636eSQL\u8bed\u53e5\u83b7\u53d6\u52a8\u6001\u7684\u6570\u636e\u96c6\uff0c\u5e76\u4e3a\u5176\u547d\u540d\u3011\uff0c\u7528\u6237\u4f7f\u7528\u65f6\u53ea\u9700\u4f7f\u7528\u3010\u540d\u79f0\u3011\u5373\u53ef\u83b7\u53d6\u7ed3\u679c\u96c6\uff0c\u53ef\u4ee5\u5c06\u8be5\u7ed3\u679c\u96c6\u5f53\u505a\u8868\u6765\u4f7f\u7528\u3002<\/p>\n\n\n\n<p id=\"ud3c450c5\">\u4f7f\u7528\u89c6\u56fe\u6211\u4eec\u53ef\u4ee5\u628a\u67e5\u8be2\u8fc7\u7a0b\u4e2d\u7684\u4e34\u65f6\u8868\u6458\u51fa\u6765\uff0c\u7528\u89c6\u56fe\u53bb\u5b9e\u73b0\uff0c\u8fd9\u6837\u4ee5\u540e\u518d\u60f3\u64cd\u4f5c\u8be5\u4e34\u65f6\u8868\u7684\u6570\u636e\u65f6\u5c31\u65e0\u9700\u91cd\u5199\u590d\u6742\u7684sql\u4e86\uff0c\u76f4\u63a5\u53bb\u89c6\u56fe\u4e2d\u67e5\u627e\u5373\u53ef\uff0c\u4f46\u89c6\u56fe\u6709\u660e\u663e\u7684\u6548\u7387\u95ee\u9898\uff0c\u5e76\u4e14\u89c6\u56fe\u662f\u5b58\u653e\u5728\u6570\u636e\u5e93\u4e2d\u7684\uff0c\u5982\u679c\u6211\u4eec\u7a0b\u5e8f\u4e2d\u4f7f\u7528\u7684sql\u8fc7\u5206\u4f9d\u8d56\u6570\u636e\u5e93\u4e2d\u7684\u89c6\u56fe\uff0c\u5373\u5f3a\u8026\u5408\uff0c\u90a3\u5c31\u610f\u5473\u7740\u6269\u5c55sql\u6781\u4e3a\u4e0d\u4fbf\uff0c\u56e0\u6b64\u5e76\u4e0d\u63a8\u8350\u4f7f\u7528\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"64768ca8\">1. \u4e24\u5f20\u6709\u5173\u7cfb\u7684\u8868<\/h4>\n\n\n\n<pre id=\"8cc692be\" class=\"wp-block-code\"><code>mysql&gt; select * from course;\n+-----+--------+------------+\n| cid | cname  | teacher_id |\n+-----+--------+------------+\n|   1 | \u751f\u7269   |          1 |\n|   2 | \u7269\u7406   |          2 |\n|   3 | \u4f53\u80b2   |          3 |\n|   4 | \u7f8e\u672f   |          2 |\n+-----+--------+------------+\n4 rows in set (0.00 sec)\n\nmysql&gt; select * from teacher;\n+-----+-----------------+\n| tid | tname           |\n+-----+-----------------+\n|   1 | \u5f20\u78ca\u8001\u5e08        |\n|   2 | \u674e\u5e73\u8001\u5e08        |\n|   3 | \u5218\u6d77\u71d5\u8001\u5e08      |\n|   4 | \u6731\u4e91\u6d77\u8001\u5e08      |\n|   5 | \u674e\u6770\u8001\u5e08        |\n+-----+-----------------+\n5 rows in set (0.00 sec)<\/code><\/pre>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"cc5705c0\">2. \u67e5\u8be2\u674e\u5e73\u8001\u5e08\u6559\u6388\u7684\u8bfe\u7a0b\u540d<\/h4>\n\n\n\n<pre id=\"5983b9ef\" class=\"wp-block-code\"><code>mysql&gt; select cname from course where teacher_id = (select tid from teacher where tname='\u674e\u5e73\u8001\u5e08');\n+--------+\n| cname  |\n+--------+\n| \u7269\u7406   |\n| \u7f8e\u672f   |\n+--------+\n2 rows in set (0.00 sec)\n\n# \u5b50\u67e5\u8be2\u51fa\u4e34\u65f6\u8868\uff0c\u4f5c\u4e3ateacher_id\u7b49\u5224\u65ad\u4f9d\u636e\nselect tid from teacher where tname='\u674e\u5e73\u8001\u5e08'<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"d6d0970b\">\u4e00 \u521b\u5efa\u89c6\u56fe<\/h3>\n\n\n\n<pre id=\"079aaa5d\" class=\"wp-block-code\"><code># \u8bed\u6cd5\uff1aCREATE VIEW \u89c6\u56fe\u540d\u79f0 AS SQL\u8bed\u53e5\ncreate view teacher_view as select tid from teacher where tname='\u674e\u5e73\u8001\u5e08';\n\n# \u4e8e\u662f\u67e5\u8be2\u674e\u5e73\u8001\u5e08\u6559\u6388\u7684\u8bfe\u7a0b\u540d\u7684sql\u53ef\u4ee5\u6539\u5199\u4e3a\nmysql&gt; select cname from course where teacher_id = (select tid from teacher_view);\n+--------+\n| cname  |\n+--------+\n| \u7269\u7406   |\n| \u7f8e\u672f   |\n+--------+\n2 rows in set (0.00 sec)<\/code><\/pre>\n\n\n\n<p id=\"u1de15cbf\"><strong>\u6ce8\u610f<\/strong>\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>\u4f7f\u7528\u89c6\u56fe\u4ee5\u540e\u5c31\u65e0\u9700\u6bcf\u6b21\u90fd\u91cd\u5199\u5b50\u67e5\u8be2\u7684sql\uff0c\u4f46\u662f\u6548\u7387\u5e76\u4e0d\u9ad8\uff0c\u8fd8\u4e0d\u5982\u5199\u5b50\u67e5\u8be2\u7684\u6548\u7387\u9ad8\u3002<\/li>\n\n\n\n<li>\u89c6\u56fe\u662f\u5b58\u653e\u5230\u6570\u636e\u5e93\u91cc\u7684\uff0c\u5982\u679c\u7a0b\u5e8f\u4e2d\u7684sql\u8fc7\u5206\u4f9d\u8d56\u4e8e\u6570\u636e\u5e93\u4e2d\u5b58\u653e\u7684\u89c6\u56fe\uff0c\u90a3\u4e48\u4e00\u65e6sql\u9700\u8981\u4fee\u6539\u4e14\u6d89\u53ca\u5230\u89c6\u56fe\u7684\u90e8\u5206\uff0c\u5219\u5fc5\u987b\u53bb\u6570\u636e\u5e93\u4e2d\u8fdb\u884c\u4fee\u6539\uff0c\u901a\u5e38\u5728\u516c\u53f8\u4e2d\u6570\u636e\u5e93\u6709\u4e13\u95e8\u7684DBA\u8d1f\u8d23\uff0c\u8fd9\u6837\u4f1a\u4ed8\u51fa\u5927\u91cf\u7684\u6c9f\u901a\u6210\u672c\uff0c\u6781\u5176\u4e0d\u65b9\u4fbf\u3002<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"aa20a167\">\u4e8c \u4f7f\u7528\u89c6\u56fe<\/h3>\n\n\n\n<pre id=\"1f0321ee\" class=\"wp-block-code\"><code># \u4fee\u6539\u89c6\u56fe\uff0c\u539f\u59cb\u8868\u4e5f\u8ddf\u7740\u6539\nmysql&gt; select * from course;\n+-----+--------+------------+\n| cid | cname  | teacher_id |\n+-----+--------+------------+\n|   1 | \u751f\u7269   |          1 |\n|   2 | \u7269\u7406   |          2 |\n|   3 | \u4f53\u80b2   |          3 |\n|   4 | \u7f8e\u672f   |          2 |\n+-----+--------+------------+\n4 rows in set (0.00 sec)\n\nmysql&gt; create view course_view as select * from course; # \u521b\u5efa\u8868course\u7684\u89c6\u56fe\nQuery OK, 0 rows affected (0.52 sec)\n\nmysql&gt; select * from course_view;\n+-----+--------+------------+\n| cid | cname  | teacher_id |\n+-----+--------+------------+\n|   1 | \u751f\u7269   |          1 |\n|   2 | \u7269\u7406   |          2 |\n|   3 | \u4f53\u80b2   |          3 |\n|   4 | \u7f8e\u672f   |          2 |\n+-----+--------+------------+\n4 rows in set (0.00 sec)\n\nmysql&gt; update course_view set cname='xxx'; # \u66f4\u65b0\u89c6\u56fe\u4e2d\u7684\u6570\u636e\nQuery OK, 4 rows affected (0.04 sec)\nRows matched: 4  Changed: 4  Warnings: 0\n\nmysql&gt; insert into course_view values(5,'yyy',2); # \u5f80\u89c6\u56fe\u4e2d\u63d2\u5165\u6570\u636e\nQuery OK, 1 row affected (0.03 sec)\n\nmysql&gt; select * from course; # \u53d1\u73b0\u539f\u59cb\u8868\u7684\u8bb0\u5f55\u4e5f\u8ddf\u7740\u4fee\u6539\u4e86\n+-----+-------+------------+\n| cid | cname | teacher_id |\n+-----+-------+------------+\n|   1 | xxx   |          1 |\n|   2 | xxx   |          2 |\n|   3 | xxx   |          3 |\n|   4 | xxx   |          2 |\n|   5 | yyy   |          2 |\n+-----+-------+------------+\n5 rows in set (0.00 sec)<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"011a7b1f\">\u4e09 \u4fee\u6539\u89c6\u56fe<\/h3>\n\n\n\n<pre id=\"e3bfe267\" class=\"wp-block-code\"><code># \u8bed\u6cd5\uff1aALTER VIEW \u89c6\u56fe\u540d\u79f0 AS SQL\u8bed\u53e5\nmysql&gt; alter view teacher_view as select * from course where cid&gt;3;\nQuery OK, 0 rows affected (0.04 sec)\n\nmysql&gt; select * from teacher_view;\n+-----+-------+------------+\n| cid | cname | teacher_id |\n+-----+-------+------------+\n|   4 | xxx   |          2 |\n|   5 | yyy   |          2 |\n+-----+-------+------------+\n2 rows in set (0.00 sec)<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"f3fd66f7\">\u56db \u5220\u9664\u89c6\u56fe<\/h3>\n\n\n\n<pre id=\"107930af\" class=\"wp-block-code\"><code># \u8bed\u6cd5\uff1aDROP VIEW \u89c6\u56fe\u540d\u79f0\nDROP VIEW teacher_view;<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u4e00 \u89c6\u56fe \u89c6\u56fe\u662f\u4e00\u4e2a\u865a\u62df\u8868\uff08\u975e\u771f\u5b9e\u5b58\u5728\uff09\uff0c\u5176\u672c\u8d28\u662f\u3010\u6839\u636eSQL\u8bed\u53e5\u83b7\u53d6\u52a8\u6001\u7684\u6570\u636e\u96c6\uff0c\u5e76\u4e3a\u5176\u547d\u540d\u3011\uff0c\u7528\u6237\u4f7f\u7528\u65f6\u53ea [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,12],"tags":[],"class_list":["post-220","post","type-post","status-publish","format-standard","hentry","category-mysql","category-sql"],"_links":{"self":[{"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=\/wp\/v2\/posts\/220","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=220"}],"version-history":[{"count":2,"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=\/wp\/v2\/posts\/220\/revisions"}],"predecessor-version":[{"id":222,"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=\/wp\/v2\/posts\/220\/revisions\/222"}],"wp:attachment":[{"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=220"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=220"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zhaoyanqi.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=220"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}