{"id":6601,"date":"2021-06-29T13:08:22","date_gmt":"2021-06-29T05:08:22","guid":{"rendered":"https:\/\/www.gbase8.cn\/?p=6601"},"modified":"2021-06-29T13:09:16","modified_gmt":"2021-06-29T05:09:16","slug":"clickhouse%e6%94%af%e6%8c%81%e7%9a%84%e8%b7%b3%e6%95%b0-%e7%a8%80%e7%96%8f%e7%b4%a2%e5%bc%95data-skipping-indexes%e4%bb%8b%e7%bb%8d","status":"publish","type":"post","link":"https:\/\/www.gbase8.cn\/en\/6601","title":{"rendered":"Clickhouse\u652f\u6301\u7684\u8df3\u6570\/\u7a00\u758f\u7d22\u5f15(Data Skipping Indexes)\u4ecb\u7ecd"},"content":{"rendered":"<p>\u5f53\u524d\u7684Clickhosue\u7248\u672c\uff08ClickHouse release 21.6, 2021-06-05\uff09\u652f\u63015\u79cd\u8df3\u6570\u3001\u7a00\u758f\u7d22\u5f15(Data Skipping Indexes)\uff0c\u672c\u6587\u4ecb\u7ecd\u5176\u4f7f\u7528\u65b9\u6cd5\u3002<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Directory Navigation<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-6a2b1f4a46a29\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-6a2b1f4a46a29\"  aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.gbase8.cn\/en\/6601\/#%E8%B7%B3%E6%95%B0%E7%A8%80%E7%96%8F%E7%B4%A2%E5%BC%95%E8%AF%AD%E6%B3%95\" >\u8df3\u6570\/\u7a00\u758f\u7d22\u5f15\u8bed\u6cd5<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.gbase8.cn\/en\/6601\/#%E8%B7%B3%E6%95%B0%E7%A8%80%E7%96%8F%E7%B4%A2%E5%BC%95%E7%B1%BB%E5%9E%8B\" >\u8df3\u6570\/\u7a00\u758f\u7d22\u5f15\u7c7b\u578b<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.gbase8.cn\/en\/6601\/#minmax\" >minmax<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.gbase8.cn\/en\/6601\/#setmax_rows\" >set(max_rows)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.gbase8.cn\/en\/6601\/#ngrambf_v1n_size_of_bloom_filter_in_bytes_number_of_hash_functions_random_seed\" >ngrambf_v1(n, size_of_bloom_filter_in_bytes, number_of_hash_functions, random_seed)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.gbase8.cn\/en\/6601\/#tokenbf_v1size_of_bloom_filter_in_bytes_number_of_hash_functions_random_seed\" >tokenbf_v1(size_of_bloom_filter_in_bytes, number_of_hash_functions, random_seed)<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E8%B7%B3%E6%95%B0%E7%A8%80%E7%96%8F%E7%B4%A2%E5%BC%95%E8%AF%AD%E6%B3%95\"><\/span>\u8df3\u6570\/\u7a00\u758f\u7d22\u5f15\u8bed\u6cd5<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u5728\u5efa\u8868\u8bed\u53e5\u7684create\u90e8\u5206\uff0c\u6307\u5b9a\u8df3\u6570\u7d22\u5f15(Data Skipping Indexes)\uff0c\u5982\u6709\u591a\u4e2a\u5219\u7528\u9017\u53f7\u5206\u5272\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>INDEX index_name expr TYPE type(...) GRANULARITY granularity_value<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\"><li>index_name : \u8df3\u6570\u7d22\u5f15\u7684\u540d\u5b57<\/li><li>expr \uff1a \u8ba1\u7b97\u8868\u8fbe\u5f0f\uff0c\u7528\u4e8e\u7d22\u5f15\u3002<\/li><li>type(...) \uff1a \u8df3\u6570\u7d22\u5f15\u7c7b\u578b<\/li><li>granularity_value \uff1a \u7c92\u5ea6\u5927\u5c0f\uff0c\u5355\u4f4d\u662f\u5f15\u64ce\u53c2\u6570<code>index_granularity<\/code>&nbsp;\u3002\u6bd4\u5982\u5927\u5c0f\u4e3a3\uff0c\u5219\u662f\u63073\u4e2a<code>index_granularity<\/code>&nbsp;\u6570\u636e\u3002\u7c92\u5ea6\u8d8a\u5927\uff0c\u8df3\u8fc7\u5927\u7247\u3010\u4e0d\u6ee1\u8db3\u3011\u8981\u6c42\u7684\u6570\u636e\u7684\u6548\u679c\u8d8a\u597d\uff0c\u4f46\u5982\u679c\u592a\u5927\uff0c\u5bfc\u81f4\u5927\u90e8\u5206\u90fd\u3010\u6ee1\u8db3\u3011\uff0c\u5219\u8df3\u8fc7\u6548\u679c\u8f83\u5c11\uff0c\u7d22\u5f15\u5c31\u5931\u53bb\u6548\u679c\u4e86\u3002<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E8%B7%B3%E6%95%B0%E7%A8%80%E7%96%8F%E7%B4%A2%E5%BC%95%E7%B1%BB%E5%9E%8B\"><\/span>\u8df3\u6570\/\u7a00\u758f\u7d22\u5f15\u7c7b\u578b<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"minmax\"><\/span>minmax<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u62a5\u9519\u7684\u6700\u5927\u6700\u5c0f\u503c\uff08\u6781\u503c)\u3002\u5982\u4e0b\u4f8b\u5b50\u662f2\u4e2a\u5217\u76f8\u4e58\uff0c\u8bb0\u5f55\u5176minmax\u503c\u7684\u8df3\u6570\u7d22\u5f15\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>INDEX a (u64 * i32, s) TYPE minmax GRANULARITY 3,<\/code><\/pre>\n\n\n\n<p>\u9002\u5408\u573a\u666f<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>SELECT count() FROM table WHERE u64 * i32 == 10<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"setmax_rows\"><\/span>set(max_rows)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u4e00\u7ec4\u6570\u91cf\u6709\u9650\u7684(max_rows)\u7684\u552f\u4e00\u6570\u7ed3\u679c\u96c6\u3002\u5982\u4e0b\u662f\u4e00\u4e2a\u5b57\u6bb5\u548c\u53e6\u4e00\u4e2a\u5b57\u6bb5\u957f\u5ea6\u7684\u4e58\u79ef\u3002 \u6700\u591a\u67091000\u4e2a\u4e0d\u91cd\u590d\u503c\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>INDEX b (u64 * length(s)) TYPE set(1000) GRANULARITY 4<\/code><\/pre>\n\n\n\n<p>\u9002\u5408\u573a\u666f<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>SELECT count() FROM table WHERE u64 * length(s) &gt;= 1234<\/code><\/pre>\n\n\n\n<p>\u6839\u636engram\u5207\u5206\u7684\u5e03\u9686\u8fc7\u6ee4\u5668\u3002\u53ef\u7528\u4e8e\u4f18\u5316&nbsp;<code>equals<\/code>&nbsp;\uff0c&nbsp;<code>like<\/code>&nbsp;\u548c&nbsp;<code>in<\/code>&nbsp;\u8868\u8fbe\u5f0f\u7684\u6027\u80fd\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"ngrambf_v1n_size_of_bloom_filter_in_bytes_number_of_hash_functions_random_seed\"><\/span>ngrambf_v1(n, size_of_bloom_filter_in_bytes, number_of_hash_functions, random_seed)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<ul class=\"wp-block-list\"><li><code>n<\/code>&nbsp;\u2013 \u77ed\u8bed\u957f\u5ea6\u3002<\/li><li><code>size_of_bloom_filter_in_bytes<\/code>&nbsp;\u2013 \u5e03\u9686\u8fc7\u6ee4\u5668\u5927\u5c0f\uff0c\u5355\u4f4d\u5b57\u8282\u3002\uff08\u56e0\u4e3a\u538b\u7f29\u5f97\u597d\uff0c\u53ef\u4ee5\u6307\u5b9a\u6bd4\u8f83\u5927\u7684\u503c\uff0c\u5982 256 \u6216 512\uff09\u3002<\/li><li><code>number_of_hash_functions<\/code>&nbsp;\u2013 \u5e03\u9686\u8fc7\u6ee4\u5668\u4e2d\u4f7f\u7528\u7684\u54c8\u5e0c\u51fd\u6570\u7684\u4e2a\u6570\u3002<\/li><li><code>random_seed<\/code>&nbsp;\u2013 \u54c8\u5e0c\u51fd\u6570\u7684\u968f\u673a\u79cd\u5b50<\/li><\/ul>\n\n\n\n<p>\u6837\u4f8b<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>INDEX index_name (ID, Code) TYPE ngrambf_v1(3, 256, 2, 0) GRANULARITY 5;\n-- 3: token \u957f\u5ea6\uff0c\u628a\u6570\u636e\u5207\u5272\u6210\u957f\u5ea6\u4e3a 3 \u7684\u77ed\u8bed\n-- 256: \u5e03\u9686\u8fc7\u6ee4\u5668\u5927\u5c0f\n-- 2: \u54c8\u5e0c\u51fd\u6570\u4e2a\u6570\n-- 0: \u54c8\u5e0c\u51fd\u6570\u968f\u673a\u79cd\u5b50<\/code><\/pre>\n\n\n\n<p>\u9002\u5408\u573a\u666f<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>where code like  '%123%'<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"tokenbf_v1size_of_bloom_filter_in_bytes_number_of_hash_functions_random_seed\"><\/span>tokenbf_v1(size_of_bloom_filter_in_bytes, number_of_hash_functions, random_seed)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u4e0engrambf_v1\u4e00\u6837\uff0c\u4e0d\u540c\u4e8e ngrams \u5b58\u50a8\u5b57\u7b26\u4e32\u6307\u5b9a\u957f\u5ea6\u7684\u6240\u6709\u7247\u6bb5\u3002\u5b83\u53ea\u5b58\u50a8\u88ab\u975e\u5b57\u6bcd\u6570\u5b57\u5b57\u7b26\u5206\u5272\u7684\u7247\u6bb5\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>INDEX d ID TYPE tokenbf_v1(256, 2, 0) GRANULARITY 5<\/code><\/pre>","protected":false},"excerpt":{"rendered":"<p>\u5f53\u524d\u7684Clickhosue\u7248\u672c\uff08ClickHouse release 21.6, 2021-06-05\uff09\u652f\u63015\u79cd\u8df3\u6570\u3001\u7a00\u758f\u7d22\u5f15(Data Skipping Indexes)\uff0c\u672c\u6587\u4ecb\u7ecd\u5176\u4f7f\u7528\u65b9\u6cd5\u3002<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[86],"tags":[],"class_list":["post-6601","post","type-post","status-publish","format-standard","hentry","category-clickhouse"],"_links":{"self":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/6601","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/comments?post=6601"}],"version-history":[{"count":16,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/6601\/revisions"}],"predecessor-version":[{"id":6720,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/6601\/revisions\/6720"}],"wp:attachment":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/media?parent=6601"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/categories?post=6601"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/tags?post=6601"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}