{"id":101868,"date":"2026-09-07T18:09:04","date_gmt":"2026-09-07T10:09:04","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/101868.html"},"modified":"2026-09-07T18:09:04","modified_gmt":"2026-09-07T10:09:04","slug":"go-%e5%90%8e%e7%ab%af%e5%bc%80%e5%8f%91%e5%ae%9e%e6%88%98%ef%bc%885%ef%bc%89%ef%bc%9a%e6%95%b0%e6%8d%ae%e5%ba%93%e6%93%8d%e4%bd%9c%e4%b8%8e-orm","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/101868.html","title":{"rendered":"Go \u540e\u7aef\u5f00\u53d1\u5b9e\u6218\uff085\uff09\uff1a\u6570\u636e\u5e93\u64cd\u4f5c\u4e0e ORM"},"content":{"rendered":"

\u4e0a\u4e00\u7bc7\u628a Handler\u3001service\u3001repository \u5206\u5f00，\u672c\u7bc7\u628a repository \u4ece\u62bd\u8c61\u63a5\u53e3\u63a8\u8fdb\u5230\u53ef\u843d\u5730\u7684\u6570\u636e\u8bbf\u95ee\u5c42\u3002\u91cd\u70b9\u4e0d\u662f\u80cc\u8bf5\u67d0\u4e2a ORM \u7684\u65b9\u6cd5\u540d，\u800c\u662f\u5efa\u7acb\u4e00\u5957\u6362\u6570\u636e\u5e93\u3001\u6362\u9a71\u52a8\u751a\u81f3\u6682\u65f6\u6362\u56de\u5185\u5b58\u5b9e\u73b0\u65f6\u4ecd\u6210\u7acb\u7684\u8fb9\u754c：\u4e1a\u52a1\u5c42\u53ea\u8ba4\u8bc6\u9886\u57df\u9519\u8bef\u548c\u4e8b\u52a1\u7528\u4f8b，\u9002\u914d\u5668\u8d1f\u8d23 SQL\u3001\u8fde\u63a5\u4e0e\u9a71\u52a8\u9519\u8bef\u3002\u6211\u4eec\u5148\u7406\u89e3 database\/sql \u7684\u8d44\u6e90\u6a21\u578b，\u518d\u786e\u5b9a\u4e8b\u52a1\u5f52\u5c5e，\u6700\u540e\u8bf4\u660e GORM \u5e94\u8be5\u9690\u85cf\u54ea\u4e9b\u91cd\u590d\u52b3\u52a8\u3001\u53c8\u6709\u54ea\u4e9b\u884c\u4e3a\u7edd\u4e0d\u80fd\u9690\u85cf\u3002<\/p>\n

\u4e00\u3001\u5148\u638c\u63e1 database\/sql \u7684\u8d44\u6e90\u6a21\u578b<\/h3>\n

sql.DB \u4e0d\u662f\u5355\u6761\u8fde\u63a5，\u800c\u662f\u5e76\u53d1\u5b89\u5168\u7684\u8fde\u63a5\u6c60\u53e5\u67c4，\u5e94\u5728\u8fdb\u7a0b\u542f\u52a8\u65f6\u521b\u5efa\u5e76\u957f\u671f\u590d\u7528\u3002\u6bcf\u4e2a\u8bf7\u6c42\u65b0\u5efa DB \u4f1a\u5931\u53bb\u6c60\u5316\u5e76\u8017\u5c3d\u6570\u636e\u5e93\u8fde\u63a5\u3002sql.Open \u901a\u5e38\u53ea\u6821\u9a8c\u53c2\u6570，\u4e0d\u4fdd\u8bc1\u5df2\u8fde\u901a；\u542f\u52a8\u68c0\u67e5\u53ef\u7528\u5e26\u8d85\u65f6 context \u7684 PingContext，readiness \u5219\u8981\u907f\u514d\u9ad8\u9891\u63a2\u6d4b\u653e\u5927\u6545\u969c\u3002<\/p>\n

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\u901a\u8fc7 SetMaxOpenConns \u9650\u5236\u603b\u8fde\u63a5，\u6570\u503c\u8981\u4e0e\u6570\u636e\u5e93\u4e0a\u9650\u3001\u5b9e\u4f8b\u6570\u91cf\u548c\u7ba1\u7406\u8fde\u63a5\u9884\u7b97\u5171\u540c\u8ba1\u7b97\u3002\u4f8b\u5982\u6570\u636e\u5e93\u5141\u8bb8 100 \u6761\u4e1a\u52a1\u8fde\u63a5\u3001\u90e8\u7f72 4 \u4e2a\u526f\u672c，\u4e0d\u80fd\u6bcf\u4e2a\u526f\u672c\u90fd\u914d 100\u3002SetMaxIdleConns \u51cf\u5c11\u53cd\u590d\u5efa\u8fde，SetConnMaxLifetime \u8ba9\u8fde\u63a5\u5728\u4ee3\u7406\u6216\u670d\u52a1\u7aef\u751f\u547d\u5468\u671f\u4e4b\u524d\u8f6e\u6362\u3002\u89c2\u5bdf DB.Stats() \u7684 WaitCount\u3001WaitDuration，\u800c\u4e0d\u662f\u51ed\u611f\u89c9\u52a0\u6c60\u3002<\/p>\n

\u4e00\u4e2a\u53ef\u8fc1\u79fb\u7684\u4f30\u7b97\u65b9\u6cd5\u662f\u5148\u9884\u7559\u8fc1\u79fb\u5de5\u5177\u3001\u76d1\u63a7\u548c\u4eba\u5de5\u6392\u969c\u8fde\u63a5，\u518d\u628a\u5269\u4f59\u989d\u5ea6\u9664\u4ee5\u5e94\u7528\u6700\u5927\u526f\u672c\u6570，\u800c\u4e0d\u662f\u5f53\u524d\u526f\u672c\u6570\u3002\u538b\u6d4b\u65f6\u540c\u65f6\u8bb0\u5f55\u8bf7\u6c42\u5ef6\u8fdf\u548c\u6c60\u7b49\u5f85：\u82e5\u6570\u636e\u5e93 CPU \u5f88\u4f4e\u800c WaitDuration \u4e0a\u5347，\u6c60\u53ef\u80fd\u504f\u5c0f；\u82e5\u6570\u636e\u5e93\u5df2\u9971\u548c，\u7ee7\u7eed\u52a0\u8fde\u63a5\u53ea\u4f1a\u5236\u9020\u66f4\u591a\u5e76\u53d1\u6392\u961f\u3002\u8fde\u63a5\u6c60\u914d\u7f6e\u56e0\u6b64\u5c5e\u4e8e\u5bb9\u91cf\u6a21\u578b\u7684\u4e00\u90e8\u5206，\u5e94\u8ddf\u968f\u90e8\u7f72\u914d\u7f6e\u8fdb\u5165\u8bc4\u5ba1，\u800c\u4e0d\u662f\u6563\u843d\u5728\u4ee3\u7801\u5e38\u91cf\u91cc\u3002<\/p>\n

\u67e5\u8be2\u5fc5\u987b\u4f7f\u7528\u5360\u4f4d\u7b26\u7ed1\u5b9a\u53c2\u6570，\u4e0d\u80fd\u7528\u5b57\u7b26\u4e32\u62fc\u63a5\u7528\u6237\u8f93\u5165\u3002PostgreSQL \u5e38\u7528 $1，MySQL \u5e38\u7528 ?，\u5dee\u5f02\u5c5e\u4e8e\u9002\u914d\u5668\u3002QueryContext \u8fd4\u56de\u7684 Rows \u8981\u5173\u95ed，\u5e76\u5728\u8fed\u4ee3\u540e\u68c0\u67e5 rows.Err()；\u5355\u884c\u67e5\u8be2\u7528 QueryRowContext，\u5176\u9519\u8bef\u5728 Scan \u65f6\u51fa\u73b0\u3002NULL \u9700\u8981 sql.NullString \u7b49\u663e\u5f0f\u8868\u8fbe，\u4e0d\u80fd\u65e0\u610f\u8bc6\u6620\u5c04\u4e3a\u7a7a\u5b57\u7b26\u4e32\u3002<\/p>\n

\u626b\u63cf\u7ed3\u679c\u65f6\u5efa\u8bae\u663e\u5f0f\u5217\u51fa\u5b57\u6bb5，\u907f\u514d SELECT * \u5728\u8fc1\u79fb\u589e\u52a0\u5217\u540e\u7834\u574f Scan \u987a\u5e8f\u3002\u6570\u636e\u884c\u4e0d\u5b58\u5728\u5e94\u7ffb\u8bd1\u4e3a\u7a33\u5b9a\u7684 ErrNotFound，\u552f\u4e00\u952e\u51b2\u7a81\u7ffb\u8bd1\u4e3a ErrConflict，\u5176\u4ed6\u9519\u8bef\u4fdd\u7559\u539f\u56e0\u5e76\u589e\u52a0\u64cd\u4f5c\u4e0a\u4e0b\u6587，\u4f8b\u5982\u201cfind user by email\u201d\u3002service \u636e\u6b64\u51b3\u5b9a 404\u3001409 \u6216 500，\u4e0d\u80fd\u8bfb\u53d6\u67d0\u4e2a PostgreSQL \u9a71\u52a8\u7684\u9519\u8bef\u5b57\u7b26\u4e32\u3002\u8fd9\u4e2a\u7ffb\u8bd1\u5c42\u6b63\u662f repository \u8ba9\u4e1a\u52a1\u4ee3\u7801\u8de8\u5b58\u50a8\u8fc1\u79fb\u7684\u4ef7\u503c\u3002<\/p>\n

\u4e0b\u9762\u4ee5 repository \u5951\u7ea6\u548c\u5185\u5b58\u5b9e\u73b0\u5c55\u793a\u552f\u4e00\u7ea6\u675f\u4e0e\u9632\u5fa1\u6027\u8fd4\u56de\u3002\u4ee3\u7801\u72ec\u7acb\u8fd0\u884c，\u4e0b\u4e00\u6bb5\u518d\u628a\u4e8b\u52a1\u539f\u7406\u843d\u5230\u53ef\u6267\u884c\u72b6\u6001\u673a\u3002<\/p>\n

package<\/span> main<\/p>\n

import<\/span> (<\/span>
\n"context"<\/span>
\n"errors"<\/span>
\n"fmt"<\/span>
\n"strings"<\/span>
\n)<\/span><\/p>\n

var<\/span> ErrConflict =<\/span> errors.<\/span>New<\/span>(<\/span>"email conflict"<\/span>)<\/span>
\ntype<\/span> User struct<\/span> {<\/span> ID int<\/span>;<\/span> Email string<\/span> }<\/span>
\ntype<\/span> UserRepository interface<\/span> {<\/span>
\nCreate<\/span>(<\/span>context.<\/span>Context,<\/span> User)<\/span> (<\/span>User,<\/span> error<\/span>)<\/span>
\nFindByEmail<\/span>(<\/span>context.<\/span>Context,<\/span> string<\/span>)<\/span> (<\/span>User,<\/span> bool<\/span>)<\/span>
\n}<\/span>
\ntype<\/span> MemoryUsers struct<\/span> {<\/span> next int<\/span>;<\/span> byEmail map<\/span>[<\/span>string<\/span>]<\/span>User }<\/span><\/p>\n

func<\/span> (<\/span>m *<\/span>MemoryUsers)<\/span> Create<\/span>(<\/span>_<\/span> context.<\/span>Context,<\/span> user User)<\/span> (<\/span>User,<\/span> error<\/span>)<\/span> {<\/span>
\nkey :=<\/span> strings.<\/span>ToLower<\/span>(<\/span>user.<\/span>Email)<\/span>
\nif<\/span> _<\/span>,<\/span> exists :=<\/span> m.<\/span>byEmail[<\/span>key]<\/span>;<\/span> exists {<\/span> return<\/span> User{<\/span>}<\/span>,<\/span> ErrConflict }<\/span>
\nm.<\/span>next++<\/span>
\nuser.<\/span>ID =<\/span> m.<\/span>next
\nm.<\/span>byEmail[<\/span>key]<\/span> =<\/span> user
\nreturn<\/span> user,<\/span> nil<\/span>
\n}<\/span>
\nfunc<\/span> (<\/span>m *<\/span>MemoryUsers)<\/span> FindByEmail<\/span>(<\/span>_<\/span> context.<\/span>Context,<\/span> email string<\/span>)<\/span> (<\/span>User,<\/span> bool<\/span>)<\/span> {<\/span>
\nuser,<\/span> ok :=<\/span> m.<\/span>byEmail[<\/span>strings.<\/span>ToLower<\/span>(<\/span>email)<\/span>]<\/span>
\nreturn<\/span> user,<\/span> ok
\n}<\/span>
\nfunc<\/span> main<\/span>(<\/span>)<\/span> {<\/span>
\nrepo :=<\/span> &<\/span>MemoryUsers{<\/span>byEmail:<\/span> make<\/span>(<\/span>map<\/span>[<\/span>string<\/span>]<\/span>User)<\/span>}<\/span>
\nfirst,<\/span> _<\/span> :=<\/span> repo.<\/span>Create<\/span>(<\/span>context.<\/span>Background<\/span>(<\/span>)<\/span>,<\/span> User{<\/span>Email:<\/span> "a@example.com"<\/span>}<\/span>)<\/span>
\n_<\/span>,<\/span> err :=<\/span> repo.<\/span>Create<\/span>(<\/span>context.<\/span>Background<\/span>(<\/span>)<\/span>,<\/span> User{<\/span>Email:<\/span> "A@example.com"<\/span>}<\/span>)<\/span>
\nfound,<\/span> ok :=<\/span> repo.<\/span>FindByEmail<\/span>(<\/span>context.<\/span>Background<\/span>(<\/span>)<\/span>,<\/span> "a@example.com"<\/span>)<\/span>
\nfmt.<\/span>Printf<\/span>(<\/span>"created=%d found=%t same=%t conflict=%t\\\\n"<\/span>,<\/span> first.<\/span>ID,<\/span> ok,<\/span> found.<\/span>ID ==<\/span> first.<\/span>ID,<\/span> errors.<\/span>Is<\/span>(<\/span>err,<\/span> ErrConflict)<\/span>)<\/span>
\n}<\/span><\/p>\n

\u8fd0\u884c\u8f93\u51fa：<\/p>\n

created=1 found=true same=true conflict=true<\/p>\n

\u4e8c\u3001\u4e8b\u52a1\u8fb9\u754c\u7531\u4e1a\u52a1\u7528\u4f8b\u51b3\u5b9a<\/h3>\n

\u4e8b\u52a1\u4e0d\u662f repository \u6bcf\u4e2a\u65b9\u6cd5\u5404\u81ea\u5f00\u542f，\u800c\u662f\u8986\u76d6\u5fc5\u987b\u539f\u5b50\u5b8c\u6210\u7684\u4e1a\u52a1\u7528\u4f8b\u3002\u4f8b\u5982\u6263\u5e93\u5b58\u4e0e\u521b\u5efa\u8ba2\u5355\u5fc5\u987b\u540c\u6210\u540c\u8d25，service \u5e94\u901a\u8fc7\u4e8b\u52a1\u6267\u884c\u5668\u8ba9\u4e24\u4e2a\u64cd\u4f5c\u4f7f\u7528\u540c\u4e00\u4e2a *sql.Tx\u3002\u4e8b\u52a1\u5185\u6240\u6709\u67e5\u8be2\u90fd\u5fc5\u987b\u8d70 Tx，\u8bef\u7528\u5168\u5c40 DB \u4f1a\u9003\u51fa\u4e8b\u52a1\u3002\u63d0\u4ea4\u5931\u8d25\u4e5f\u8981\u8fd4\u56de\u9519\u8bef，\u4e0d\u80fd\u56e0\u4e3a\u4e1a\u52a1\u8bed\u53e5\u6210\u529f\u5c31\u5ffd\u7565 Commit\u3002<\/p>\n

\u63a8\u8350\u6a21\u5f0f\u662f BeginTx \u540e defer Rollback，\u518d\u6267\u884c\u903b\u8f91\u5e76 Commit\u3002\u5df2\u7ecf\u63d0\u4ea4\u540e Rollback \u8fd4\u56de sql.ErrTxDone，\u53ef\u5ffd\u7565\u3002context \u8d85\u65f6\u4f1a\u53d6\u6d88\u67e5\u8be2\u548c\u4e8b\u52a1，\u4f46\u6570\u636e\u5e93\u9a71\u52a8\u80fd\u5426\u7acb\u5373\u4e2d\u65ad\u53d6\u51b3\u4e8e\u5b9e\u73b0\u3002\u9694\u79bb\u7ea7\u522b\u6309\u4e0d\u53d8\u91cf\u9009\u62e9：\u9ed8\u8ba4\u7ea7\u522b\u5e38\u8db3\u591f，\u6d89\u53ca\u5e76\u53d1\u62a2\u5360\u53ef\u7528\u6761\u4ef6 UPDATE\u3001\u884c\u9501\u6216\u53ef\u91cd\u8bd5\u7684\u5e8f\u5217\u5316\u4e8b\u52a1\u3002<\/p>\n

\u4e8b\u52a1\u6267\u884c\u5668\u53ef\u4ee5\u66b4\u9732 WithinTransaction(ctx, func(Repositories) error) error，\u56de\u8c03\u62ff\u5230\u7ed1\u5b9a\u540c\u4e00\u4e2a Tx \u7684\u4ed3\u50a8\u96c6\u5408\u3002\u8fd9\u6837 service \u80fd\u8868\u8fbe\u201c\u521b\u5efa\u8ba2\u5355\u3001\u6263\u51cf\u5e93\u5b58\u3001\u5199\u5165\u5ba1\u8ba1\u4e8b\u4ef6\u201d\u662f\u4e00\u4e2a\u539f\u5b50\u7528\u4f8b，\u5374\u4e0d\u9700\u8981\u77e5\u9053 *sql.Tx\u3002\u82e5\u56e2\u961f\u89c4\u6a21\u8f83\u5c0f，\u4e5f\u53ef\u4ee5\u8ba9 service \u76f4\u63a5\u4f9d\u8d56\u4e00\u4e2a\u5f88\u7a84\u7684 DBTX \u63a5\u53e3；\u5173\u952e\u662f\u540c\u4e00\u4e8b\u52a1\u4e2d\u7684\u6240\u6709\u9002\u914d\u5668\u5171\u4eab\u6267\u884c\u53e5\u67c4，\u5e76\u4e14\u6d4b\u8bd5\u80fd\u6545\u610f\u5236\u9020\u7b2c\u4e8c\u6b65\u5931\u8d25\u6765\u9a8c\u8bc1\u7b2c\u4e00\u6b65\u6ca1\u6709\u843d\u5e93\u3002<\/p>\n

\u4e0d\u8981\u7528\u201c\u5148\u67e5\u518d\u63d2\u201d\u4fdd\u8bc1\u552f\u4e00\u6027，\u4e24\u8bf7\u6c42\u53ef\u80fd\u540c\u65f6\u67e5\u4e0d\u5230\u3002\u6570\u636e\u5e93\u552f\u4e00\u7d22\u5f15\u624d\u662f\u6700\u7ec8\u88c1\u5224，\u9002\u914d\u5668\u5c06\u9a71\u52a8\u9519\u8bef\u7ffb\u8bd1\u4e3a ErrConflict\u3002\u540c\u7406，\u5e93\u5b58\u6263\u51cf\u53ef\u5199\u6210 UPDATE … SET stock=stock-1 WHERE id=$1 AND stock>0，\u6839\u636e\u53d7\u5f71\u54cd\u884c\u6570\u5224\u65ad，\u800c\u975e\u5728\u5e94\u7528\u5185\u8bfb\u540e\u5199\u3002<\/p>\n

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\u4ee5\u4e0b\u5c0f\u7a0b\u5e8f\u7528\u5feb\u7167\u6a21\u62df\u8f6c\u8d26\u4e8b\u52a1，\u5931\u8d25\u65f6\u4e0d\u63d0\u4ea4\u3002\u5b83\u4e0d\u662f\u6570\u636e\u5e93\u66ff\u4ee3\u54c1，\u800c\u662f\u53ef\u6267\u884c\u5730\u5c55\u793a\u201c\u4fee\u6539\u526f\u672c\u3001\u9a8c\u8bc1\u4e0d\u53d8\u91cf\u3001\u539f\u5b50\u53d1\u5e03\u201d\u7684\u4e8b\u52a1\u8bed\u4e49\u3002<\/p>\n

package<\/span> main<\/p>\n

import<\/span> (<\/span>
\n"errors"<\/span>
\n"fmt"<\/span>
\n)<\/span><\/p>\n

var<\/span> ErrInsufficient =<\/span> errors.<\/span>New<\/span>(<\/span>"insufficient balance"<\/span>)<\/span>
\ntype<\/span> Ledger map<\/span>[<\/span>string<\/span>]<\/span>int<\/span><\/p>\n

func<\/span> transfer<\/span>(<\/span>current Ledger,<\/span> from,<\/span> to string<\/span>,<\/span> amount int<\/span>)<\/span> (<\/span>Ledger,<\/span> error<\/span>)<\/span> {<\/span>
\nnext :=<\/span> make<\/span>(<\/span>Ledger,<\/span> len<\/span>(<\/span>current)<\/span>)<\/span>
\nfor<\/span> account,<\/span> balance :=<\/span> range<\/span> current {<\/span> next[<\/span>account]<\/span> =<\/span> balance }<\/span>
\nif<\/span> amount <=<\/span> 0<\/span> ||<\/span> next[<\/span>from]<\/span> <<\/span> amount {<\/span> return<\/span> current,<\/span> ErrInsufficient }<\/span>
\nnext[<\/span>from]<\/span> -=<\/span> amount
\nnext[<\/span>to]<\/span> +=<\/span> amount
\nreturn<\/span> next,<\/span> nil<\/span>
\n}<\/span><\/p>\n

func<\/span> main<\/span>(<\/span>)<\/span> {<\/span>
\nledger :=<\/span> Ledger{<\/span>"alice"<\/span>:<\/span> 100<\/span>,<\/span> "bob"<\/span>:<\/span> 20<\/span>}<\/span>
\ncommitted,<\/span> err :=<\/span> transfer<\/span>(<\/span>ledger,<\/span> "alice"<\/span>,<\/span> "bob"<\/span>,<\/span> 30<\/span>)<\/span>
\nif<\/span> err ==<\/span> nil<\/span> {<\/span> ledger =<\/span> committed }<\/span>
\nfmt.<\/span>Printf<\/span>(<\/span>"after_success alice=%d bob=%d\\\\n"<\/span>,<\/span> ledger[<\/span>"alice"<\/span>]<\/span>,<\/span> ledger[<\/span>"bob"<\/span>]<\/span>)<\/span>
\ncommitted,<\/span> err =<\/span> transfer<\/span>(<\/span>ledger,<\/span> "alice"<\/span>,<\/span> "bob"<\/span>,<\/span> 1000<\/span>)<\/span>
\nif<\/span> err ==<\/span> nil<\/span> {<\/span> ledger =<\/span> committed }<\/span>
\nfmt.<\/span>Printf<\/span>(<\/span>"after_failure alice=%d bob=%d rollback=%t\\\\n"<\/span>,<\/span> ledger[<\/span>"alice"<\/span>]<\/span>,<\/span> ledger[<\/span>"bob"<\/span>]<\/span>,<\/span> errors.<\/span>Is<\/span>(<\/span>err,<\/span> ErrInsufficient)<\/span>)<\/span>
\n}<\/span><\/p>\n

\u8fd0\u884c\u8f93\u51fa：<\/p>\n

after_success alice=70 bob=50
\nafter_failure alice=70 bob=50 rollback=true<\/p>\n

\u4e09\u3001\u8ba9 ORM \u670d\u52a1\u4e8e\u67e5\u8be2\u800c\u4e0d\u662f\u9690\u85cf\u67e5\u8be2<\/h3>\n

GORM \u63d0\u4f9b\u6a21\u578b\u6620\u5c04\u3001\u5173\u8054\u3001\u94a9\u5b50\u548c\u8fc1\u79fb，\u80fd\u63d0\u9ad8\u5e38\u89c4 CRUD \u901f\u5ea6，\u4f46\u751f\u6210 SQL \u4ecd\u9700\u5ba1\u67e5\u3002\u5f00\u542f\u5f00\u53d1\u73af\u5883\u53c2\u6570\u5316\u65e5\u5fd7，\u4f7f\u7528 DryRun \u6216\u6570\u636e\u5e93\u6162\u67e5\u8be2\u65e5\u5fd7\u68c0\u67e5 SQL\u3002\u5217\u8868\u4e2d\u5faa\u73af\u52a0\u8f7d\u5173\u8054\u4f1a\u5f62\u6210 N+1：\u4e00\u6761\u5217\u8868\u67e5\u8be2\u5916\u52a0 N \u6761\u5173\u8054\u67e5\u8be2；\u7528 Preload\u3001Join \u6216\u6279\u91cf WHERE id IN (…) \u89e3\u51b3，\u5e76\u5bf9\u67e5\u8be2\u6b21\u6570\u5199\u96c6\u6210\u6d4b\u8bd5\u3002<\/p>\n

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ORM \u7684 AutoMigrate \u9002\u5408\u539f\u578b，\u4e0d\u8db3\u4ee5\u627f\u62c5\u4e25\u683c\u751f\u4ea7\u8fc1\u79fb\u3002\u751f\u4ea7\u8fc1\u79fb\u5e94\u4f7f\u7528\u6709\u7248\u672c\u3001\u53ef\u5ba1\u67e5\u7684 SQL \u5de5\u5177，\u5982 golang-migrate \u6216 Atlas；\u5148\u589e\u52a0\u517c\u5bb9\u5217\u548c\u7d22\u5f15，\u518d\u90e8\u7f72\u517c\u5bb9\u65b0\u65e7\u7ed3\u6784\u7684\u4ee3\u7801，\u6700\u540e\u6e05\u7406\u65e7\u5217\u3002\u5927\u8868\u52a0\u975e\u7a7a\u5217\u3001\u5efa\u7d22\u5f15\u548c\u6539\u7c7b\u578b\u53ef\u80fd\u9501\u8868，\u9700\u6309\u7167\u76ee\u6807\u6570\u636e\u5e93\u80fd\u529b\u8bbe\u8ba1\u5728\u7ebf\u53d8\u66f4\u3002<\/p>\n

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\u7d22\u5f15\u8bbe\u8ba1\u8981\u4ece\u5b9e\u9645\u67e5\u8be2\u53cd\u63a8\u3002WHERE tenant_id=? AND status=? ORDER BY created_at DESC,id DESC \u901a\u5e38\u9700\u8981\u4ee5\u79df\u6237\u548c\u72b6\u6001\u5f00\u5934\u3001\u6392\u5e8f\u5b57\u6bb5\u7ed3\u5c3e\u7684\u590d\u5408\u7d22\u5f15；\u53ea\u6709\u5355\u5217\u7d22\u5f15\u672a\u5fc5\u80fd\u907f\u514d\u6392\u5e8f\u3002\u4e0a\u7ebf\u524d\u7528\u76ee\u6807\u6570\u636e\u5e93\u7684 EXPLAIN \u68c0\u67e5\u8ba1\u5212，\u4e0a\u7ebf\u540e\u7ed3\u5408\u6162\u67e5\u8be2\u6837\u672c\u6821\u6b63，\u800c\u4e0d\u662f\u4e3a\u6bcf\u4e2a\u5b57\u6bb5\u673a\u68b0\u5efa\u7d22\u5f15\u3002\u7d22\u5f15\u4f1a\u5360\u7a7a\u95f4\u5e76\u589e\u52a0\u5199\u653e\u5927，\u6240\u4ee5\u6bcf\u4e2a\u7d22\u5f15\u90fd\u5e94\u80fd\u5bf9\u5e94\u4e00\u4e2a\u660e\u786e\u7684\u8bfb\u53d6\u8def\u5f84\u6216\u7ea6\u675f\u3002<\/p>\n

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\u53c2\u8003\u6765\u6e90<\/h3>\n