{"id":5278,"date":"2024-11-14T12:05:59","date_gmt":"2024-11-14T04:05:59","guid":{"rendered":"https:\/\/fwq.ai\/blog\/5278\/"},"modified":"2024-11-14T12:05:59","modified_gmt":"2024-11-14T04:05:59","slug":"mysql%e6%80%8e%e4%b9%88%e6%9f%a5%e7%9c%8b%e7%b4%a2%e5%bc%95","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/5278\/","title":{"rendered":"mysql\u600e\u4e48\u67e5\u770b\u7d22\u5f15"},"content":{"rendered":"

\u5982\u4f55\u67e5\u770b \u7d22\u5f15<\/strong><\/p>\n

\u901a\u8fc7 SHOW INDEX \u547d\u4ee4<\/strong><\/p>\n

\u6700\u5e38\u7528\u7684\u65b9\u6cd5\u662f\u4f7f\u7528 SHOW INDEX \u547d\u4ee4\u3002\u5bf9\u4e8e\u7279\u5b9a\u7684\u8868\uff0c\u8be5\u547d\u4ee4\u5c06\u663e\u793a\u6240\u6709\u5df2\u521b\u5efa\u7684\u7d22\u5f15\u3002<\/p>\n

\u8bed\u6cd5\uff1a<\/p>\n

SHOW INDEX FROM table_name;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u793a\u4f8b\uff1a<\/p>\n
SHOW INDEX FROM customers;<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u8f93\u51fa\u5c06\u5305\u542b\u4ee5\u4e0b\u5217\uff1a<\/p>\n
    \n
  • Table\uff1a\u7d22\u5f15\u6240\u5728\u7684\u8868\u540d<\/li>\n
  • Non_unique\uff1a\u6307\u793a\u7d22\u5f15\u662f\u5426\u552f\u4e00\uff080 \u8868\u793a\u552f\u4e00\uff09<\/li>\n
  • Key_name\uff1a\u7d22\u5f15\u7684\u540d\u79f0<\/li>\n
  • Seq_in_index\uff1a\u7d22\u5f15\u4e2d\u5217\u7684\u987a\u5e8f<\/li>\n
  • Column_name\uff1a\u88ab\u7d22\u5f15\u7684\u5217\u540d<\/li>\n
  • Collation\uff1a\u5217\u7684\u6392\u5e8f\u89c4\u5219<\/li>\n
  • Cardinality\uff1a\u7d22\u5f15\u4e2d\u552f\u4e00\u503c\u7684\u4f30\u8ba1\u6570\u91cf<\/li>\n
  • Sub_part\uff1a\u7d22\u5f15\u662f\u5426\u4ec5\u9002\u7528\u4e8e\u8868\u7684\u4e00\u90e8\u5206<\/li>\n<\/ul>\n
    \u901a\u8fc7 INFORMATION_SCHEMA.STATISTICS \u8868<\/strong><\/p>\n
    \u53e6\u4e00\u4e2a\u67e5\u770b\u7d22\u5f15\u7684\u65b9\u6cd5\u662f\u67e5\u8be2 INFORMATION_SCHEMA.STATISTICS \u8868\u3002\u8be5\u8868\u5b58\u50a8\u6709\u5173\u6570\u636e\u5e93\u4e2d\u6240\u6709\u8868\u7684\u7edf\u8ba1\u4fe1\u606f\uff0c\u5305\u62ec\u7d22\u5f15\u3002<\/p>\n
    \u8bed\u6cd5\uff1a<\/p>\n
    SELECT * FROM INFORMATION_SCHEMA.STATISTICS\nWHERE table_schema = 'database_name' AND table_name = 'table_name';<\/pre>\n
     \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
    \u793a\u4f8b\uff1a<\/p>\n
    SELECT * FROM INFORMATION_SCHEMA.STATISTICS\nWHERE table_schema = 'mydb' AND table_name = 'customers';<\/pre>\n
     \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
    \u8f93\u51fa\u5c06\u5305\u542b\u4ee5\u4e0b\u5217\uff1a<\/p>\n
      \n
    • TABLE_SCHEMA\uff1a\u7d22\u5f15\u6240\u5728\u6570\u636e\u5e93\u7684\u67b6\u6784\u540d<\/li>\n
    • TABLE_NAME\uff1a\u7d22\u5f15\u6240\u5728\u8868\u7684\u540d\u79f0<\/li>\n
    • INDEX_NAME\uff1a\u7d22\u5f15\u7684\u540d\u79f0<\/li>\n
    • NON_UNIQUE\uff1a\u6307\u793a\u7d22\u5f15\u662f\u5426\u552f\u4e00<\/li>\n
    • CARDINALITY\uff1a\u7d22\u5f15\u4e2d\u552f\u4e00\u503c\u7684\u4f30\u8ba1\u6570\u91cf<\/li>\n
    • COLUMN_NAME\uff1a\u88ab\u7d22\u5f15\u7684\u5217\u540d<\/li>\n<\/ul>\n
      \u4ee5\u4e0a\u5c31\u662f\u600e\u4e48\u67e5\u770b\u7d22\u5f15\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u7f51\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
      \u5982\u4f55\u67e5\u770b \u7d22\u5f15 \u901a\u8fc7 SHOW INDEX \u547d\u4ee4 \u6700\u5e38\u7528\u7684\u65b9\u6cd5\u662f\u4f7f\u7528 SHOW INDEX \u547d\u4ee4\u3002\u5bf9\u4e8e\u7279\u5b9a\u7684\u8868\uff0c\u8be5\u547d\u4ee4\u5c06\u663e\u793a\u6240\u6709\u5df2\u521b\u5efa\u7684\u7d22\u5f15\u3002 \u8bed\u6cd5\uff1a SHOW INDEX FROM table_name; \u767b\u5f55\u540e\u590d\u5236 \u793a\u4f8b\uff1a SHOW INDEX FROM customers; \u767b\u5f55\u540e\u590d\u5236 \u8f93\u51fa\u5c06\u5305\u542b\u4ee5\u4e0b\u5217\uff1a Table\uff1a\u7d22\u5f15\u6240\u5728\u7684\u8868\u540d Non_unique\uff1a\u6307\u793a\u7d22\u5f15\u662f\u5426\u552f\u4e00\uff080 \u8868\u793a\u552f\u4e00\uff09 Key_name\uff1a\u7d22\u5f15\u7684\u540d\u79f0 Seq_in_index\uff1a\u7d22\u5f15\u4e2d\u5217\u7684\u987a\u5e8f Column_name\uff1a\u88ab\u7d22\u5f15\u7684\u5217\u540d Collation\uff1a\u5217\u7684\u6392\u5e8f\u89c4\u5219 Cardinality\uff1a\u7d22\u5f15\u4e2d\u552f\u4e00\u503c\u7684\u4f30\u8ba1\u6570\u91cf Sub_part\uff1a\u7d22\u5f15\u662f\u5426\u4ec5\u9002\u7528\u4e8e\u8868\u7684\u4e00\u90e8\u5206 \u901a\u8fc7 INFORMATION_SCHEMA.STATISTICS \u8868 \u53e6\u4e00\u4e2a\u67e5\u770b\u7d22\u5f15\u7684\u65b9\u6cd5\u662f\u67e5\u8be2 INFORMATION_SCHEMA.STATISTICS \u8868\u3002\u8be5\u8868\u5b58\u50a8\u6709\u5173\u6570\u636e\u5e93\u4e2d\u6240\u6709\u8868\u7684\u7edf\u8ba1\u4fe1\u606f\uff0c\u5305\u62ec\u7d22\u5f15\u3002 \u8bed\u6cd5\uff1a SELECT * FROM INFORMATION_SCHEMA.STATISTICS WHERE table_schema = ‘database_name’ AND table_name = ‘table_name’; \u767b\u5f55\u540e\u590d\u5236 \u793a\u4f8b\uff1a SELECT * […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-5278","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5278","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=5278"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5278\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=5278"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=5278"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=5278"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}