当前位置： 首页 > news >正文

物流网站建设方案政务公开加强网站规范化建设

news 2026/4/9 21:45:58
物流网站建设方案,政务公开加强网站规范化建设,西宁网络推广服务网,建网页的公司前言 最近看到了 何登成 大佬的 深入MySQL源码 -- Step By Step 的 pdf 呵呵 似乎是找到了一些 方向 之前对于 mysql 方面的东西, 更多的仅仅是简单的使用[业务中的各种增删改查], 以及一些面试题的背诵 这里会参照 MySQL Internals Manual 来大致的看一下 i…前言  最近看到了 何登成 大佬的 深入MySQL源码 -- Step By Step 的 pdf 呵呵 似乎是找到了一些 方向  之前对于 mysql 方面的东西, 更多的仅仅是简单的使用[业务中的各种增删改查], 以及一些面试题的背诵  这里会参照 MySQL Internals Manual 来大致的看一下 innodb 里面的 page 的存储相关, 这些是深入了解 mysql 的基础  本文内容对应的是 mysql innodb record 里面的 查看一下 rec 的数据信息, 除了 rec 之外还有那些信息呢 ?  MySQL Internals Manual - 22.2 InnoDB Page Structure 以下截图参照自 MySQL Internals Manual   总的来说 Page 拆分成 FileHeader, PageHeader, Infimum Supremum, UserRecords, FreeSpace, PageDirectory, FileTrailer  FileHeader 里面主要是包含了当前文件的相关信息, 这里面的我们需要关注的就 FIL_PAGE_OFFSET, FIL_PAGE_PREV, FIL_PAGE_NEXT  PageHeader 里面主要包含的是当前 page 的元数据信息  PAGE_N_DIR_SLOTS : 当前 page pageDirectory 的数量  PAGE_HEAP_TOP : 当前 FreeSpace 的开始的偏移  PAGE_N_HEAP : 当前 page 记录的数量(UserRecords Infimum  Supremum) PAGE_FREE : 当前 page 被删除的记录数量  PAGE_FREE : 当前 page 被删除的记录占用的字节数  PAGE_LAST_INSERT : 当前 page 最后一个新增的记录的偏移  PAGE_DIRECTION : 当前 page 最后一个新增的记录的偏移  PAGE_N_DIRECTION : 当前 page 最后一个新增的记录的偏移  PAGE_N_RECS : UserRecords 记录数量  PAGE_MAX_TRX_ID : 最大的 trxId  PAGE_LEVEL : pageLevel  PAGE_INDEX_ID : pageIndexId  PAGE_BTR_SEG_LEAF : btrSegLeaf  PAGE_BTR_SEG_TOP : btrSegTop  Infimum Supremum : Page 里面两条预制的记录 infimum 和 supremum, 分别表示 record 链表逻辑上的 head 和 tail  UserRecords : 各个用户的记录信息, 可以参见 mysql innodb record  FreeSpace : 当前 page 未使用的空间  PageDirectory : key order 排序的 稀疏 record指针 列表  FilTrailer : page 的 checksum FileHeader 的 FIL_PAGE_LSN 后四字节  22.2.2 Example 里面介绍了一个实例的案例, 剖析一个实际的记录在内存中的数据分布情况, 以及拆解每一个字节的逻辑意义, 可以移步文档看一下, 这里就不截图了, 请自行查阅文档  Page 实际案例剖析  我们这里需要着重注意的是 PageHeader 的这部分的数据信息  PAGE_N_DIR_SLOTS : 当前 page pageDirectory 的数量  PAGE_HEAP_TOP : 当前 FreeSpace 的开始的偏移  PAGE_N_HEAP : 当前 page 记录的数量(UserRecords Infimum  Supremum) PAGE_FREE : 当前 page 被删除的记录数量  PAGE_FREE : 当前 page 被删除的记录占用的字节数  PAGE_LAST_INSERT : 当前 page 最后一个新增的记录的偏移  PAGE_DIRECTION : 当前 page 最后一个新增的记录的偏移  PAGE_N_DIRECTION : 当前 page 最后一个新增的记录的偏移  PAGE_N_RECS : UserRecords 记录数量  PAGE_MAX_TRX_ID : 最大的 trxId  PAGE_LEVEL : pageLevel  PAGE_INDEX_ID : pageIndexId  PAGE_BTR_SEG_LEAF : btrSegLeaf  PAGE_BTR_SEG_TOP : btrSegTop  # user 对应的数据 当前页的数据信息, 拆解 (lldb) x 0x1286cc000 -c 0x120 0x1286cc000: 10 aa fb 30 00 00 00 03 ff ff ff ff ff ff ff ff .0.... 0x1286cc010: 00 00 00 00 00 1a a2 7d 45 bf 00 00 00 00 00 00 ......}E...... 0x1286cc020: 00 00 00 00 00 06 00 02 00 b9 80 04 00 00 00 00 ............... 0x1286cc030: 00 a0 00 02 00 01 00 02 00 00 00 00 00 00 00 00 ............... 0x1286cc040: 00 00 00 00 00 00 00 00 00 16 00 00 00 06 00 00 ................ 0x1286cc050: 00 02 00 f2 00 00 00 06 00 00 00 02 00 32 01 00 ............2.. 0x1286cc060: 02 00 1c 69 6e 66 69 6d 75 6d 00 03 00 0b 00 00 ...infimum...... 0x1286cc070: 73 75 70 72 65 6d 75 6d 05 00 00 00 10 00 21 80 supremum......!. 0x1286cc080: 00 00 01 00 00 00 00 2b 07 04 00 00 01 56 04 7b ............V.{ 0x1286cc090: 80 00 00 1c 6a 65 72 72 79 04 00 00 00 18 ff d0 ....jerry..... 0x1286cc0a0: 80 00 00 02 00 00 00 00 35 04 83 00 00 01 36 01 ........5.....6. 0x1286cc0b0: 10 80 00 00 16 6c 75 63 79 00 00 00 00 00 00 00 .....lucy....... 0x1286cc0c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x1286cc0d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x1286cc0e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x1286cc0f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x1286cc100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x1286cc110: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................# page 的记录信息 0x1286cc000: 10 aa fb 30 00 00 00 03 ff ff ff ff ff ff ff ff .0.... 0x1286cc010: 00 00 00 00 00 1a a2 7d 45 bf 00 00 00 00 00 00 ......}E...... 0x1286cc020: 00 00 00 00 00 06 00 02 00 b9 80 04 00 00 00 00 ............... 0x1286cc030: 00 a0 00 02 00 01 00 02 00 00 00 00 00 00 00 00 ............... 0x1286cc040: 00 00 00 00 00 00 00 00 00 16 00 00 00 06 00 00 ................ 0x1286cc050: 00 02 00 f2 00 00 00 06 00 00 00 02 00 32 01 00 ............2..# FIL HEADERR : 38 bytes FIL_PAGE_SPACE 10 aa fb 30 FIL_PAGE_OFFSET 00 00 00 03 FIL_PAGE_PREV ff ff ff ff FIL_PAGE_NEXT ff ff ff ff FIL_PAGE_LSN 00 00 00 00 00 1a c4 cb FIL_PAGE_TYPE 45 bf FIL_PAGE_FILE_FLUSH_LSN 00 00 00 00 00 00 00 00 FIL_PAGE_ARCH_LOG_NO 00 00 00 06# PAGE_HEADER : 56 byte PAGE_N_DIR_SLOTS 00 02 PAGE_HEAP_TOP 00 b9 PAGE_N_HEAP 80 04 PAGE_FREE 00 00 PAGE_GARBAGE 00 00 PAGE_LAST_INSERT 00 a0 PAGE_DIRECTION 00 02 PAGE_N_DIRECTION 00 01 PAGE_N_RECS 00 02 PAGE_MAX_TRX_ID 00 00 00 00 00 00 00 00 PAGE_LEVEL 00 00 PAGE_INDEX_ID 00 00 00 00 00 00 00 16 PAGE_BTR_SEG_LEAF 00 00 00 06 00 00 00 02 00 f2 PAGE_BTR_SEG_TOP 00 00 00 06 00 00 00 02 00 32# Page Directory Fil Trailer, 地址不一样是因为是不同的进程里面 inspect 的, 但是不影响数据 (lldb) x 0x12663bfe0 -c 0x20 0x12663bfe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663bff0: 00 00 00 00 00 70 00 63 ac c3 1c c6 00 1a c4 cb .....p.c...PAGE_N_DIR_SLOTS [0x0070, 0x0063] FIL_PAGE_END_LSN 63 ac c3 1c c6 00 1a c4 cb CHECK_SUM ac c3 1c c6 FIL_PAGE_LSN 00 1a c4 cbUserRecords 的组织  从下面的 step2 的数据组织上来看, 我们这里的 record 列表物理上是需要 record 在 FreeSpace 里面申请 record 的空间, 但是逻辑 [以 next offset 来路由]来说 是根据 id 排序的  jerry - lucy - jerry5 - jerry7 - jerry8 - jerry9  # 这里是 原有数据 jerry, lucy # 物理上不是按照 id 进行排序的阿, 但是逻辑上来说 是按照 key order 排序的[根据 next 单链表] # 1. 先新增了 jerry7, jerry8, jerry9 INSERT INTO test.user(id, age, name) VALUES (7, 22, jerry7); INSERT INTO test.user(id, age, name) VALUES (8, 22, jerry8); INSERT INTO test.user(id, age, name) VALUES (9, 22, jerry9); # 2. 先新增了 jerry5 INSERT INTO test.user(id, age, name) VALUES (5, 22, jerry5);# step1 (lldb) x 0x12663807f -c 0x120 0x12663807f: 80 00 00 01 00 00 00 00 2b 07 04 00 00 01 56 04 .............V. 0x12663808f: 7b 80 00 00 1c 6a 65 72 72 79 04 00 00 00 18 00 {....jerry...... 0x12663809f: 20 80 00 00 02 00 00 00 00 35 04 83 00 00 01 36 ........5.....6 0x1266380af: 01 10 80 00 00 16 6c 75 63 79 06 00 00 00 20 00 ......lucy.... . 0x1266380bf: 22 80 00 00 07 00 00 00 00 3d 0b 84 00 00 01 37 .............7 0x1266380cf: 01 10 80 00 00 16 6a 65 72 72 79 37 06 00 00 00 ......jerry7.... 0x1266380df: 28 00 22 80 00 00 08 00 00 00 00 3d 0c 85 00 00 (............. 0x1266380ef: 01 38 01 10 80 00 00 16 6a 65 72 72 79 38 06 00 .8......jerry8.. 0x1266380ff: 00 00 30 ff 6c 80 00 00 09 00 00 00 00 3d 0d 86 ..0l.......... 0x12663810f: 00 00 01 39 01 10 80 00 00 16 6a 65 72 72 79 39 ...9......jerry9 0x12663811f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663812f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663813f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663814f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663815f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663816f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663817f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663818f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ # step2 (lldb) x 0x12663807f -c 0x120 0x12663807f: 80 00 00 01 00 00 00 00 2b 07 04 00 00 01 56 04 .............V. 0x12663808f: 7b 80 00 00 1c 6a 65 72 72 79 04 00 00 00 18 00 {....jerry...... 0x12663809f: 86 80 00 00 02 00 00 00 00 35 04 83 00 00 01 36 .........5.....6 0x1266380af: 01 10 80 00 00 16 6c 75 63 79 06 00 00 00 20 00 ......lucy.... . 0x1266380bf: 22 80 00 00 07 00 00 00 00 3d 0b 84 00 00 01 37 .............7 0x1266380cf: 01 10 80 00 00 16 6a 65 72 72 79 37 06 00 00 00 ......jerry7.... 0x1266380df: 28 00 22 80 00 00 08 00 00 00 00 3d 0c 85 00 00 (............. 0x1266380ef: 01 38 01 10 80 00 00 16 6a 65 72 72 79 38 06 00 .8......jerry8.. 0x1266380ff: 00 00 30 ff 6c 80 00 00 09 00 00 00 00 3d 0d 86 ..0l.......... 0x12663810f: 00 00 01 39 01 10 80 00 00 16 6a 65 72 72 79 39 ...9......jerry9 0x12663811f: 06 00 00 00 38 ff 9a 80 00 00 05 00 00 00 00 3d ....8......... 0x12663812f: 14 8a 00 00 01 91 01 10 80 00 00 16 6a 65 72 72 ............jerr 0x12663813f: 79 35 00 00 00 00 00 00 00 00 00 00 00 00 00 00 y5.............. 0x12663814f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663815f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663816f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663817f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 0x12663818f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................参考 MySQL Internals Manual mysql innodb record
http://www.w-s-a.com/news/582386/

相关文章：

  • 莆田网站建设创意自助建站英文
  • cms系统创建静态网站龙岗网站建设哪家好
  • 自己做的网站被封了邢台规划局网站建设
  • 网站建设项目合同wordpress主题没法用
  • 个旧市哪里有做网站wordpress内页php页面
  • 程序员接活的平台网站互联网平台建设方案
  • 网站安全建设模板深圳企业管理咨询公司
  • 做网站 还是淘宝店wordpress分类链接后加
  • wordpress腾讯云 COSseo内容优化心得
  • 特价旅游机票网站建设i营销
  • 如何成立网站深圳创业项目
  • 建设商业网站惠州网站建设推荐乐云seo
  • 如何申请免费域名做网站免费推广神器
  • 自媒体人专用网站安岳网站建设
  • 特乐网站建设做网站推广要多少钱
  • 山东省建设安全生产协会网站义乌跨境电商公司前十名
  • 做网站优化就是发文章吗起飞页自助建站平台的特点
  • 做网站还是做app好慈溪机械加工网
  • 上传下载文件网站开发的php源码腾讯企点
  • 给分管领导网站建设情况汇报怎么写网络运营的岗位职责及任职要求
  • 电线电缆技术支持中山网站建设广告设计培训学校有哪些
  • 如何禁止通过ip访问网站wordpress无法调用主题布局和图片
  • 江西建设工程信息网站重庆网站推广大全
  • 南浔区住房城乡建设局网站网页设计基础学什么
  • 萧山做网站的企业网站建设 西安
  • 江西省城乡建设厅网站百度站长资源平台
  • 本地搭建linux服务器做网站免费查企业信息查询
  • 电商网站建设与运营网上购物哪个网站最好
  • 做app做网站从何学起网站设计需要什么证
  • 设计网站最重要的是要有良好的短网址还原