{"id":126,"date":"2023-07-20T16:54:42","date_gmt":"2023-07-20T08:54:42","guid":{"rendered":"https:\/\/jiachen.de.cool\/blog\/?p=126"},"modified":"2023-07-20T16:54:42","modified_gmt":"2023-07-20T08:54:42","slug":"%e6%9f%a5%e6%89%be%e5%ad%97%e7%ac%a6%e4%b8%b2%e5%87%bd%e6%95%b0","status":"publish","type":"post","link":"https:\/\/jiachen.de.cool\/blog\/2023\/07\/20\/%e6%9f%a5%e6%89%be%e5%ad%97%e7%ac%a6%e4%b8%b2%e5%87%bd%e6%95%b0\/","title":{"rendered":"\u67e5\u627e\u5b57\u7b26\u4e32\u51fd\u6570"},"content":{"rendered":"\n

1\u3001\u8fd4\u56de\u5b57\u7b26\u4e32\u4f4d\u7f6e\u7684find_in_set()\u51fd\u6570<\/p>\n\n\n\n

find_in_set(str1,str2);<\/code><\/p>\n\n\n\n

\u8be5\u51fd\u6570\u4f1a\u8fd4\u56de\u5728\u5b57\u7b26\u4e32str2\u4e2d\u4e0estr1\u76f8\u5339\u914d\u7684\u5b57\u7b26\u4e32\u7684\u4f4d\u7f6e\uff0c\u53c2\u6570str2\u5b57\u7b26\u4e32\u4e2d\u5305\u542b\u82e5\u5e72\u4e2a\u7528\u9017\u53f7\u9694\u5f00\u7684\u5b57\u7b26\u4e32\u3002<\/p>\n\n\n\n

mysql> select find_in_set('mysql','oracle,mysql,db2');\n+-----------------------------------------+\n| find_in_set('mysql','oracle,mysql,db2') |\n+-----------------------------------------+\n|                                       2 |\n+-----------------------------------------+\n1 row in set (0.10 sec)\n\nmysql> select find_in_set('mysql','oracle,wonita,db2');\/*\u8fd4\u56de0\uff0c\u4e0d\u662f\u8fd4\u56deNULL*\/\n+------------------------------------------+\n| find_in_set('mysql','oracle,wonita,db2') |\n+------------------------------------------+\n|                                        0 |\n+------------------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select find_in_set('mysql','oracle,mysql   ,db2');\/*\u7a7a\u683c\u6709\u6548*\/\n+--------------------------------------------+\n| find_in_set('mysql','oracle,mysql   ,db2') |\n+--------------------------------------------+\n|                                          0 |\n+--------------------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select find_in_set('mysql','oracle,  mysql,db2');\/*\u7a7a\u683c\u6709\u6548*\/\n+-------------------------------------------+\n| find_in_set('mysql','oracle,  mysql,db2') |\n+-------------------------------------------+\n|                                         0 |\n+-------------------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select find_in_set('mysql','oracle,mysql,db2,mysql');\/*\u8fd4\u56de\u7b2c\u4e00\u4e2a\u5339\u914d\u7684\u4f4d\u7f6e*\/\n+-----------------------------------------------+\n| find_in_set('mysql','oracle,mysql,db2,mysql') |\n+-----------------------------------------------+\n|                                             2 |\n+-----------------------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select find_in_set('mysql  ','oracle,mysql  ,db2');\/*\u7a7a\u683c\u6709\u6548*\/\n+---------------------------------------------+\n| find_in_set('mysql  ','oracle,mysql  ,db2') |\n+---------------------------------------------+\n|                                           2 |\n+---------------------------------------------+\n1 row in set (0.00 sec)<\/code><\/pre>\n\n\n\n
2\u3001\u8fd4\u56de\u6307\u5b9a\u5b57\u7b26\u4e32\u4f4d\u7f6e\u7684field()\u51fd\u6570<\/p>\n\n\n\n
field(str,str1,str2,...);<\/code><\/p>\n\n\n\n
\u8be5\u51fd\u6570\u8fd4\u56de\u7b2c\u4e00\u4e2a\u4e0e\u5b57\u7b26\u4e32str\u5339\u914d\u7684\u5b57\u7b26\u4e32\u7684\u4f4d\u7f6e\u3002<\/p>\n\n\n\n
mysql> select field('mysql','oracle','db2','redis','mysql');\n+-----------------------------------------------+\n| field('mysql','oracle','db2','redis','mysql') |\n+-----------------------------------------------+\n|                                             4 |\n+-----------------------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select field('mysql','mysql  ','db2','redis');\\*\u5b57\u7b26\u540e\u9762\u7684\u7a7a\u683c\u88ab\u5ffd\u7565\u6389*\\\n+----------------------------------------+\n| field('mysql','mysql  ','db2','redis') |\n+----------------------------------------+\n|                                      1 |\n+----------------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select field('mysql','db2','  mysql','redis','mysql');\\*\u5b57\u7b26\u524d\u9762\u7684\u7a7a\u683c\u6ca1\u6709\u88ab\u5ffd\u7565*\\\n+------------------------------------------------+\n| field('mysql','db2','  mysql','redis','mysql') |\n+------------------------------------------------+\n|                                              4 |\n+------------------------------------------------+\n1 row in set (0.00 sec)<\/code><\/pre>\n\n\n\n
3\u3001\u8fd4\u56de\u6307\u5b9a\u4f4d\u7f6e\u7684\u5b57\u7b26\u4e32\u7684elt()\u51fd\u6570<\/p>\n\n\n\n
elt(n,str1,str2,...);<\/code><\/p>\n\n\n\n
mysql> select elt(1,'mysql','db2','oracle');\n+-------------------------------+\n| elt(1,'mysql','db2','oracle') |\n+-------------------------------+\n| mysql                         |\n+-------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select elt(0,'mysql','db2','oracle');\/*\u8d85\u51fa\u8fd4\u56de\u8303\u56f4*\/\n+-------------------------------+\n| elt(0,'mysql','db2','oracle') |\n+-------------------------------+\n| NULL                          |\n+-------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select elt(4,'mysql','db2','oracle');\/*\u8d85\u51fa\u8fd4\u56de\u8303\u56f4*\/\n+-------------------------------+\n| elt(4,'mysql','db2','oracle') |\n+-------------------------------+\n| NULL                          |\n+-------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select length(elt(1,'mysql  ','db2','oracle'));\/*\u7a7a\u683c\u88ab\u8f93\u51fa*\/\n+-----------------------------------------+\n| length(elt(1,'mysql  ','db2','oracle')) |\n+-----------------------------------------+\n|                                       7 |\n+-----------------------------------------+\n1 row in set (0.00 sec)\n\nmysql> select length(elt(1,'  mysql  ','db2','oracle'));\/*\u7a7a\u683c\u88ab\u8f93\u51fa*\/\n+-------------------------------------------+\n| length(elt(1,'  mysql  ','db2','oracle')) |\n+-------------------------------------------+\n|                                         9 |\n+-------------------------------------------+\n1 row in set (0.00 sec)<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
1\u3001\u8fd4\u56de\u5b57\u7b26\u4e32\u4f4d\u7f6e\u7684find_in_set()\u51fd\u6570 find_in_set(str1,str2); \u8be5\u51fd\u6570\u4f1a\u8fd4… <\/p>\n
Read the full article<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[20,27],"class_list":["post-126","post","type-post","status-publish","format-standard","hentry","category-mysql","tag-20","tag-27"],"_links":{"self":[{"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/posts\/126","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/comments?post=126"}],"version-history":[{"count":1,"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/posts\/126\/revisions"}],"predecessor-version":[{"id":127,"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/posts\/126\/revisions\/127"}],"wp:attachment":[{"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/media?parent=126"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/categories?post=126"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jiachen.de.cool\/blog\/wp-json\/wp\/v2\/tags?post=126"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}