{"id":207460,"date":"2025-07-08T12:54:23","date_gmt":"2025-07-08T04:54:23","guid":{"rendered":"https:\/\/server.hk\/cnblog\/207460\/"},"modified":"2025-07-08T12:54:23","modified_gmt":"2025-07-08T04:54:23","slug":"%e5%b0%86%e6%95%b0%e6%8d%ae%e5%ba%93%e7%bb%93%e6%9e%9c%e6%89%ab%e6%8f%8f%e5%88%b0%e5%b5%8c%e5%a5%97%e7%bb%93%e6%9e%84%e6%95%b0%e7%bb%84%e4%b8%ad","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/207460\/","title":{"rendered":"\u5c06\u6570\u636e\u5e93\u7ed3\u679c\u626b\u63cf\u5230\u5d4c\u5957\u7ed3\u6784\u6570\u7ec4\u4e2d"},"content":{"rendered":"

<\/b> <\/p>\n

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> \u5c06\u6570\u636e\u5e93\u7ed3\u679c\u626b\u63cf\u5230\u5d4c\u5957\u7ed3\u6784\u6570\u7ec4\u4e2d<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-04-22 20:00:37<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u672c\u7bc7\u6587\u7ae0\u4e3b\u8981\u662f\u7ed3\u5408\u6211\u4e4b\u524d\u9762\u8bd5\u7684\u5404\u79cd\u7ecf\u5386\u548c\u5b9e\u6218\u5f00\u53d1\u4e2d\u9047\u5230\u7684\u95ee\u9898\u89e3\u51b3\u7ecf\u9a8c\u6574\u7406\u7684\uff0c\u5e0c\u671b\u8fd9\u7bc7\u300a\u5c06\u6570\u636e\u5e93\u7ed3\u679c\u626b\u63cf\u5230\u5d4c\u5957\u7ed3\u6784\u6570\u7ec4\u4e2d\u300b\u5bf9\u4f60\u6709\u5f88\u5927\u5e2e\u52a9\uff01\u6b22\u8fce\u6536\u85cf\uff0c\u5206\u4eab\u7ed9\u66f4\u591a\u7684\u9700\u8981\u7684\u670b\u53cb\u5b66\u4e60~<\/p>\n

\u95ee\u9898\u5185\u5bb9
\n <\/p>\n

\u6211\u5e0c\u671b\u5c06\u6570\u636e\u5e93\u8fde\u63a5\u7684\u7ed3\u679c\u626b\u63cf\u5230\u7ed3\u6784\u6570\u7ec4\u4e2d\uff0c\u5176\u4e2d\u8fd8\u5305\u62ec\u5d4c\u5957\u7ed3\u6784\u6570\u7ec4\u3002\u4f46\u662f\uff0c\u5f53\u626b\u63cf\u7ed3\u679c\u5e76\u4e14\u5d4c\u5957\u6570\u7ec4\u7684\u5207\u7247\u4e2d\u7684\u503c\u5168\u90e8\u4e3a\u96f6\u65f6…\u8be5\u5207\u7247\u4e0d\u4f1a\u7701\u7565\u7a7a\u3002\u5047\u8bbe\u6570\u7ec4\u7b2c\u4e8c\u4e2a\u4f4d\u7f6e\u7684\u5207\u7247\u5145\u6ee1\u96f6\u503c\u3002\u6211\u4ecd\u7136\u6709\u8be5\u5207\u7247\u7684 {}<\/code> \u8f93\u51fa\u3002\u6211\u5c1d\u8bd5\u521b\u5efa\u9876\u7ea7\u7ed3\u6784 users<\/code> \u7684\u7a7a\u5207\u7247\uff0c\u4f46\u968f\u540e\u629b\u51fa\u9519\u8bef\uff1a index[0] out of range<\/code> \u5e76\u4e14\u6211\u53d1\u73b0\u81ea\u5df1\u9677\u5165\u4e86\u5faa\u73af\u3002\u6ca1\u6709\u770b\u5230\u4e0e\u8fd9\u4e2a\u7279\u5b9a\u95ee\u9898\u76f8\u5173\u7684\u4efb\u4f55\u5185\u5bb9\uff0c\u6211\u770b\u5230\u4e86\u6709\u5173\u5d4c\u5957\u7ed3\u6784\u7684\u95ee\u9898\uff0c\u4f46\u6ca1\u6709\u770b\u5230\u6709\u5173\u5d4c\u5957\u7ed3\u6784\u6570\u7ec4\u7684\u95ee\u9898\u3002\u6709\u4ec0\u4e48\u5e2e\u52a9\u8ba9\u5207\u7247\u7701\u7565\uff1f<\/p>\n

\u662f\u7684\uff0c\u6211\u7684\u7ed3\u6784\u6807\u7b7e\u4e2d\u786e\u5b9e\u6709 omitempty<\/code> \u3002<\/p>\n

package main\n\nimport (\n    \"database\/sql\"\n    _ \"github.com\/go-sql-driver\/mysql\"\n    \"log\"\n)\n\ntype User struct {\n    Id       int64 `json:\",omitempty\"`\n    Username string `json:\",omitempty\"`\n    Email    string `json:\",omitempty\"`\n    Profile  []*Profile `json:\",omitempty\"`\n}\n\ntype Profile struct {\n    Id        int64  `json:\",omitempty\"`\n    UserId    int64  `json:\",omitempty\"`\n    Firstname *string `json:\",omitempty\"`\n    Lastname  *string `json:\",omitempty\"`\n}\n\nvar DB *sql.DB\n\nfunc checkErr(err error, msg string) {\n    if err != nil {\n        log.Fatal(msg, err)\n    }\n}\n\nfunc main() {\n    DB, _ = sql.Open(\"mysql\", \"username:secrect@\/database\")\n    defer DB.Close()\n\n}\n\n\nfunc GetUsers() {\n    stmt, err := DB.Query(\"Select users.id, username , email , firstname AS firstName1 , lastname AS lastName1, firstname AS firstName2 , lastname AS lastName2 from users left join profiles on users.id = profiles.user_id \")\n    if err != nil {\n        panic(err.Error())\n    }\n    defer stmt.Close()\n\n    users := []User{}\n\n    for stmt.Next() {\n        user := User{Profile: Profile{{}}}\n        err := stmt.Scan(&user.Id, &user.Username, &user.Email, &user.Profile[0].Firstname, &user.Profile[0].Lastname, &user.Profile[1].Firstname, &user.Profile[1].Lastname)\n        if err != nil {\n            panic(err.Error())\n        }\n\n        users = append(users, user)\n    }\n}<\/pre>\n
 <\/p>\n
\u89e3\u51b3\u65b9\u6848<\/h2>\n
 <\/p>\n
\u60a8\u6b63\u5728\u5c1d\u8bd5\u5c06\u57fa\u4e8e\u884c\u7684 sql \u67e5\u8be2\u7684\u7ed3\u679c\u96c6\u52a0\u8f7d\u5230\u4e0d\u57fa\u4e8e\u884c\u7684\u591a\u7ea7\u6570\u636e\u7ed3\u6784\u4e2d\u3002\u60a8\u53ef\u4ee5\u5904\u7406\u8054\u63a5\u7684\u7ed3\u679c\u96c6\u5e76\u586b\u5199\u7ed3\u6784\uff0c\u4e5f\u53ef\u4ee5\u6267\u884c\u4e24\u4e2a\u67e5\u8be2\uff0c\u4e00\u4e2a\u67e5\u8be2\u7528\u4e8e\u83b7\u53d6 user<\/code>\uff0c\u53e6\u4e00\u4e2a\u67e5\u8be2\u7528\u4e8e\u83b7\u53d6\u4e0e\u5176\u5173\u8054\u7684 profile<\/code>s\u3002<\/p>\n
\u60a8\u7684\u7ed3\u679c\u96c6\u5c06\u5305\u542b\u6bcf\u4e2a\u7528\u6237\u7684\u591a\u884c\uff0c\u56e0\u6b64\u60a8\u5fc5\u987b\u5904\u7406\u7ed3\u679c\u5e76\u6839\u636e\u60a8\u83b7\u53d6\u7684\u7ed3\u679c\u6784\u5efa\u7ed3\u6784\u3002\u50cf\u8fd9\u6837\u7684\u4e1c\u897f\u5e94\u8be5\u6709\u6548\uff1a<\/p>\n
for stmt.Next() {\n      var userId, userName, userEmail, firstName, lastName string\n         err := stmt.Scan(&userId, &userName, &userEmail, &firstName,&lastName)\n        if err != nil {\n            panic(err.Error())\n        }\n        user:=findUser(users,userId)\n        if user==nil {\n           \/\/ Add new user\n           user:=&User{Id:userId,Name:userName,Email:userEmail}\n           \/\/ Add user to users\n        }\n        user.Profiles=append(user.Profiles,&Profile{\/* Fill profile fields here*\/}))\n\n    }<\/pre>\n
\u60a8\u63d0\u5230\u7684 json \u6807\u7b7e\u4ec5\u9002\u7528\u4e8e json \u7f16\u7ec4\/\u89e3\u7ec4\u3002\u5b83\u4eec\u4e0e\u6570\u636e\u5e93\u64cd\u4f5c\u65e0\u5173\u3002<\/p>\n
\u7ec8\u4e8e\u4ecb\u7ecd\u5b8c\u5566\uff01\u5c0f\u4f19\u4f34\u4eec\uff0c\u8fd9\u7bc7\u5173\u4e8e\u300a\u5c06\u6570\u636e\u5e93\u7ed3\u679c\u626b\u63cf\u5230\u5d4c\u5957\u7ed3\u6784\u6570\u7ec4\u4e2d\u300b\u7684\u4ecb\u7ecd\u5e94\u8be5\u8ba9\u4f60\u6536\u83b7\u591a\u591a\u4e86\u5427\uff01\u6b22\u8fce\u5927\u5bb6\u6536\u85cf\u6216\u5206\u4eab\u7ed9\u66f4\u591a\u9700\u8981\u5b66\u4e60\u7684\u670b\u53cb\u5427~\u516c\u4f17\u53f7\u4e5f\u4f1a\u53d1\u5e03Golang\u76f8\u5173\u77e5\u8bc6\uff0c\u5feb\u6765\u5173\u6ce8\u5427\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5f53\u524d\u4f4d\u7f6e\uff1a > > ...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-207460","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207460","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=207460"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207460\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=207460"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=207460"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=207460"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}