<!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width,initial-scale=1">
    <title> </title>
    <meta name="generator" content="VuePress 1.8.2">
    <link rel="icon" href="/favicon.ico">
    <meta name="description" content=" ">
    <meta name="Description" content="Apache IoTDB: Time Series Database for IoT">
    <meta name="Keywords" content="TSDB, time series, time series database, IoTDB, IoT database, IoT data management,时序数据库, 时间序列管理, IoTDB, 物联网数据库, 实时数据库, 物联网数据管理, 物联网数据">
    <meta name="baidu-site-verification" content="wfKETzB3OT">
    <meta name="google-site-verification" content="mZWAoRY0yj_HAr-s47zHCGHzx5Ju-RVm5wDbPnwQYFo">
    
    <link rel="preload" href="/assets/css/0.styles.c79f5191.css" as="style"><link rel="preload" href="/assets/js/app.150a3d30.js" as="script"><link rel="preload" href="/assets/js/3.96a076a8.js" as="script"><link rel="preload" href="/assets/js/4.a65360c5.js" as="script"><link rel="preload" href="/assets/js/35.135cd75d.js" as="script"><link rel="prefetch" href="/assets/js/10.9afb0814.js"><link rel="prefetch" href="/assets/js/100.af381a82.js"><link rel="prefetch" href="/assets/js/101.48333335.js"><link rel="prefetch" href="/assets/js/102.0c3cc894.js"><link rel="prefetch" href="/assets/js/103.a49d810c.js"><link rel="prefetch" href="/assets/js/104.8bee529c.js"><link rel="prefetch" href="/assets/js/105.36d3f834.js"><link rel="prefetch" href="/assets/js/106.8902c844.js"><link rel="prefetch" href="/assets/js/107.04fb3d26.js"><link rel="prefetch" href="/assets/js/108.207f1626.js"><link rel="prefetch" href="/assets/js/109.ce41e6ee.js"><link rel="prefetch" href="/assets/js/11.e6c21699.js"><link rel="prefetch" href="/assets/js/110.df86daa1.js"><link rel="prefetch" href="/assets/js/111.c053c3a7.js"><link rel="prefetch" href="/assets/js/112.1f92e6d5.js"><link rel="prefetch" href="/assets/js/113.c10a1424.js"><link rel="prefetch" href="/assets/js/114.11bce2f0.js"><link rel="prefetch" href="/assets/js/115.528cda1d.js"><link rel="prefetch" href="/assets/js/116.763ead1d.js"><link rel="prefetch" href="/assets/js/117.34441361.js"><link rel="prefetch" href="/assets/js/118.c2814fb8.js"><link rel="prefetch" href="/assets/js/119.9cb28ed2.js"><link rel="prefetch" href="/assets/js/12.26a10771.js"><link rel="prefetch" href="/assets/js/120.284d437e.js"><link rel="prefetch" href="/assets/js/121.e260fdd5.js"><link rel="prefetch" href="/assets/js/122.8b9eeb18.js"><link rel="prefetch" href="/assets/js/123.66aea25f.js"><link rel="prefetch" href="/assets/js/124.98088358.js"><link rel="prefetch" href="/assets/js/125.670b8f46.js"><link rel="prefetch" href="/assets/js/126.e27b939f.js"><link rel="prefetch" href="/assets/js/127.e2174de8.js"><link rel="prefetch" href="/assets/js/128.be400387.js"><link rel="prefetch" href="/assets/js/129.ecc36529.js"><link rel="prefetch" href="/assets/js/13.15f5baec.js"><link rel="prefetch" href="/assets/js/130.e4ba4653.js"><link rel="prefetch" href="/assets/js/131.c7f4eeb7.js"><link rel="prefetch" href="/assets/js/132.13c30a00.js"><link rel="prefetch" href="/assets/js/133.144beb94.js"><link rel="prefetch" href="/assets/js/134.2f28174c.js"><link rel="prefetch" href="/assets/js/135.a5b90019.js"><link rel="prefetch" href="/assets/js/136.778020e6.js"><link rel="prefetch" href="/assets/js/137.99f730ef.js"><link rel="prefetch" href="/assets/js/138.98781e3d.js"><link rel="prefetch" href="/assets/js/139.781af6f3.js"><link rel="prefetch" href="/assets/js/14.a526cf0d.js"><link rel="prefetch" href="/assets/js/140.822b8074.js"><link rel="prefetch" href="/assets/js/141.20b83742.js"><link rel="prefetch" href="/assets/js/142.530ac198.js"><link rel="prefetch" href="/assets/js/143.dd87b7e6.js"><link rel="prefetch" href="/assets/js/144.844e572a.js"><link rel="prefetch" href="/assets/js/145.e5c77329.js"><link rel="prefetch" href="/assets/js/146.4a7ae59b.js"><link rel="prefetch" href="/assets/js/147.a36d24ee.js"><link rel="prefetch" href="/assets/js/148.d5237710.js"><link rel="prefetch" href="/assets/js/149.0140fefc.js"><link rel="prefetch" href="/assets/js/15.b8d48dd6.js"><link rel="prefetch" href="/assets/js/150.40cf45ea.js"><link rel="prefetch" href="/assets/js/151.bc1a5f4a.js"><link rel="prefetch" href="/assets/js/152.70704187.js"><link rel="prefetch" href="/assets/js/153.5ac6bb17.js"><link rel="prefetch" href="/assets/js/154.ab6bebcf.js"><link rel="prefetch" href="/assets/js/155.5b50c888.js"><link rel="prefetch" href="/assets/js/156.8c5d0506.js"><link rel="prefetch" href="/assets/js/157.92c5a429.js"><link rel="prefetch" href="/assets/js/158.6fa4828c.js"><link rel="prefetch" href="/assets/js/159.dad828da.js"><link rel="prefetch" href="/assets/js/16.22ec18ce.js"><link rel="prefetch" href="/assets/js/160.de548190.js"><link rel="prefetch" href="/assets/js/161.6ba35dd2.js"><link rel="prefetch" href="/assets/js/162.64aec67d.js"><link rel="prefetch" href="/assets/js/163.ac66ae3c.js"><link rel="prefetch" href="/assets/js/164.9f666631.js"><link rel="prefetch" href="/assets/js/165.4e5bd458.js"><link rel="prefetch" href="/assets/js/166.0aa8b0f4.js"><link rel="prefetch" href="/assets/js/167.dfa60ab3.js"><link rel="prefetch" href="/assets/js/168.a2b08bc6.js"><link rel="prefetch" href="/assets/js/169.79bf8b2d.js"><link rel="prefetch" href="/assets/js/17.eb113894.js"><link rel="prefetch" href="/assets/js/170.851fd688.js"><link rel="prefetch" href="/assets/js/171.fc20c330.js"><link rel="prefetch" href="/assets/js/172.0f8c2891.js"><link rel="prefetch" href="/assets/js/173.ec01b740.js"><link rel="prefetch" href="/assets/js/174.a3d1d693.js"><link rel="prefetch" href="/assets/js/175.15c0a659.js"><link rel="prefetch" href="/assets/js/176.dd7027bf.js"><link rel="prefetch" href="/assets/js/177.49e0584d.js"><link rel="prefetch" href="/assets/js/178.00bff1e4.js"><link rel="prefetch" href="/assets/js/179.002322c9.js"><link rel="prefetch" href="/assets/js/18.268b0005.js"><link rel="prefetch" href="/assets/js/180.a7abb866.js"><link rel="prefetch" href="/assets/js/181.52afb246.js"><link rel="prefetch" href="/assets/js/182.af025d86.js"><link rel="prefetch" href="/assets/js/183.718514b3.js"><link rel="prefetch" href="/assets/js/184.765cd602.js"><link rel="prefetch" href="/assets/js/185.b90b2c4b.js"><link rel="prefetch" href="/assets/js/186.6bb5c726.js"><link rel="prefetch" href="/assets/js/187.cf2d1963.js"><link rel="prefetch" href="/assets/js/188.1a21c282.js"><link rel="prefetch" href="/assets/js/189.6011e8e6.js"><link rel="prefetch" href="/assets/js/19.554dfad4.js"><link rel="prefetch" href="/assets/js/190.3c06913e.js"><link rel="prefetch" href="/assets/js/191.8adbbe16.js"><link rel="prefetch" href="/assets/js/192.017dd4e6.js"><link rel="prefetch" href="/assets/js/193.7ccaec75.js"><link rel="prefetch" href="/assets/js/194.8f9041de.js"><link rel="prefetch" href="/assets/js/195.fd720578.js"><link rel="prefetch" href="/assets/js/196.96bcf363.js"><link rel="prefetch" href="/assets/js/197.cd9b0c3a.js"><link rel="prefetch" href="/assets/js/198.d7d53c65.js"><link rel="prefetch" href="/assets/js/199.231713be.js"><link rel="prefetch" href="/assets/js/20.4b3311fd.js"><link rel="prefetch" href="/assets/js/200.7a7d4178.js"><link rel="prefetch" href="/assets/js/201.2ba7d87e.js"><link rel="prefetch" href="/assets/js/202.aeecfa26.js"><link rel="prefetch" href="/assets/js/203.31d144e8.js"><link rel="prefetch" href="/assets/js/204.a435a4df.js"><link rel="prefetch" href="/assets/js/205.bdb53d1c.js"><link rel="prefetch" href="/assets/js/206.127ef777.js"><link rel="prefetch" href="/assets/js/207.b98cce82.js"><link rel="prefetch" href="/assets/js/208.17f8c242.js"><link rel="prefetch" href="/assets/js/209.7537428f.js"><link rel="prefetch" href="/assets/js/21.c90f33d7.js"><link rel="prefetch" href="/assets/js/210.bb097df5.js"><link rel="prefetch" href="/assets/js/211.58f61280.js"><link rel="prefetch" href="/assets/js/212.2a8a092d.js"><link rel="prefetch" href="/assets/js/213.27b01fce.js"><link rel="prefetch" href="/assets/js/214.20fc09c1.js"><link rel="prefetch" href="/assets/js/215.6a5be256.js"><link rel="prefetch" href="/assets/js/216.0898f799.js"><link rel="prefetch" href="/assets/js/217.4a74ae6f.js"><link rel="prefetch" href="/assets/js/218.aba2c019.js"><link rel="prefetch" href="/assets/js/219.7a59585f.js"><link rel="prefetch" href="/assets/js/22.7a1f06fe.js"><link rel="prefetch" href="/assets/js/220.ed26afb4.js"><link rel="prefetch" href="/assets/js/221.2a04d9af.js"><link rel="prefetch" href="/assets/js/222.88ff1449.js"><link rel="prefetch" href="/assets/js/223.e0731710.js"><link rel="prefetch" href="/assets/js/224.d4234a51.js"><link rel="prefetch" href="/assets/js/225.781fbf0c.js"><link rel="prefetch" href="/assets/js/226.b4a6eadb.js"><link rel="prefetch" href="/assets/js/227.e474974a.js"><link rel="prefetch" href="/assets/js/228.9cf4477d.js"><link rel="prefetch" href="/assets/js/229.770de8aa.js"><link rel="prefetch" href="/assets/js/23.67190bee.js"><link rel="prefetch" href="/assets/js/230.38a49e3f.js"><link rel="prefetch" href="/assets/js/231.d568c4d5.js"><link rel="prefetch" href="/assets/js/232.166bfa5d.js"><link rel="prefetch" href="/assets/js/233.53776299.js"><link rel="prefetch" href="/assets/js/234.893211e1.js"><link rel="prefetch" href="/assets/js/235.98e38acf.js"><link rel="prefetch" href="/assets/js/236.d975a1d2.js"><link rel="prefetch" href="/assets/js/237.ea10ef6b.js"><link rel="prefetch" href="/assets/js/238.af5a633b.js"><link rel="prefetch" href="/assets/js/239.57483628.js"><link rel="prefetch" href="/assets/js/24.d99ae084.js"><link rel="prefetch" href="/assets/js/240.8c8b0bca.js"><link rel="prefetch" href="/assets/js/241.4dd02a1f.js"><link rel="prefetch" href="/assets/js/242.7581d50b.js"><link rel="prefetch" href="/assets/js/243.8020ea53.js"><link rel="prefetch" href="/assets/js/244.37b38c56.js"><link rel="prefetch" href="/assets/js/245.99393763.js"><link rel="prefetch" href="/assets/js/246.b06e6e3c.js"><link rel="prefetch" href="/assets/js/247.638b4d9a.js"><link rel="prefetch" href="/assets/js/248.536526ef.js"><link rel="prefetch" href="/assets/js/249.fd9ae868.js"><link rel="prefetch" href="/assets/js/25.06c13d3c.js"><link rel="prefetch" href="/assets/js/250.d34aa7ca.js"><link rel="prefetch" href="/assets/js/251.bee51cc9.js"><link rel="prefetch" href="/assets/js/252.d05db63c.js"><link rel="prefetch" href="/assets/js/253.1d1d3f0d.js"><link rel="prefetch" href="/assets/js/254.c03b32fe.js"><link rel="prefetch" href="/assets/js/255.96af022a.js"><link rel="prefetch" href="/assets/js/256.ae0db25f.js"><link rel="prefetch" href="/assets/js/257.a1ce9d72.js"><link rel="prefetch" href="/assets/js/258.8e6e0acb.js"><link rel="prefetch" href="/assets/js/259.cace667d.js"><link rel="prefetch" href="/assets/js/26.960d4740.js"><link rel="prefetch" href="/assets/js/260.4ad02a23.js"><link rel="prefetch" href="/assets/js/261.65705a16.js"><link rel="prefetch" href="/assets/js/262.c1701c29.js"><link rel="prefetch" href="/assets/js/263.827ffcc8.js"><link rel="prefetch" href="/assets/js/264.da67695a.js"><link rel="prefetch" href="/assets/js/265.cc127de2.js"><link rel="prefetch" href="/assets/js/266.eb1a8f54.js"><link rel="prefetch" href="/assets/js/267.5a9302f2.js"><link rel="prefetch" href="/assets/js/268.77576299.js"><link rel="prefetch" href="/assets/js/269.c502d05d.js"><link rel="prefetch" href="/assets/js/27.70f7dc1a.js"><link rel="prefetch" href="/assets/js/270.e5ee9893.js"><link rel="prefetch" href="/assets/js/271.72666635.js"><link rel="prefetch" href="/assets/js/272.cee600f4.js"><link rel="prefetch" href="/assets/js/273.d56fdf7a.js"><link rel="prefetch" href="/assets/js/274.6d98103d.js"><link rel="prefetch" href="/assets/js/275.8ba6ba62.js"><link rel="prefetch" href="/assets/js/276.fedf9586.js"><link rel="prefetch" href="/assets/js/277.63502fbf.js"><link rel="prefetch" href="/assets/js/278.fa0cf0cb.js"><link rel="prefetch" href="/assets/js/279.c1e5ae29.js"><link rel="prefetch" href="/assets/js/28.830d54da.js"><link rel="prefetch" href="/assets/js/280.d5f0dac6.js"><link rel="prefetch" href="/assets/js/281.cb43a1c2.js"><link rel="prefetch" href="/assets/js/282.197d5892.js"><link rel="prefetch" href="/assets/js/283.ed1f376b.js"><link rel="prefetch" href="/assets/js/284.7f612c82.js"><link rel="prefetch" href="/assets/js/285.25425d04.js"><link rel="prefetch" href="/assets/js/286.452285ab.js"><link rel="prefetch" href="/assets/js/287.be955f5e.js"><link rel="prefetch" href="/assets/js/288.16a3e78c.js"><link rel="prefetch" href="/assets/js/289.8b6d8bfb.js"><link rel="prefetch" href="/assets/js/29.1b108016.js"><link rel="prefetch" href="/assets/js/290.4b148797.js"><link rel="prefetch" href="/assets/js/291.b62aac54.js"><link rel="prefetch" href="/assets/js/292.7e57c52e.js"><link rel="prefetch" href="/assets/js/293.f6dfbee6.js"><link rel="prefetch" href="/assets/js/294.2d922951.js"><link rel="prefetch" href="/assets/js/295.1917bfde.js"><link rel="prefetch" href="/assets/js/296.d6fa961c.js"><link rel="prefetch" href="/assets/js/297.c787acaf.js"><link rel="prefetch" href="/assets/js/298.d558df1b.js"><link rel="prefetch" href="/assets/js/299.e77a794b.js"><link rel="prefetch" href="/assets/js/30.b06debf2.js"><link rel="prefetch" href="/assets/js/300.bdfdc245.js"><link rel="prefetch" href="/assets/js/301.030c03f2.js"><link rel="prefetch" href="/assets/js/302.af97980a.js"><link rel="prefetch" href="/assets/js/303.f1971e49.js"><link rel="prefetch" href="/assets/js/304.0494314e.js"><link rel="prefetch" href="/assets/js/305.4a4f3e67.js"><link rel="prefetch" href="/assets/js/306.572ff5ba.js"><link rel="prefetch" href="/assets/js/307.016778c9.js"><link rel="prefetch" href="/assets/js/308.b1d4a83e.js"><link rel="prefetch" href="/assets/js/309.40c22ea7.js"><link rel="prefetch" href="/assets/js/31.abfdfce0.js"><link rel="prefetch" href="/assets/js/310.03604f1e.js"><link rel="prefetch" href="/assets/js/311.85a79804.js"><link rel="prefetch" href="/assets/js/312.350317ac.js"><link rel="prefetch" href="/assets/js/313.afd1a236.js"><link rel="prefetch" href="/assets/js/314.2eff0e13.js"><link rel="prefetch" href="/assets/js/315.32c84a51.js"><link rel="prefetch" href="/assets/js/316.ec650494.js"><link rel="prefetch" href="/assets/js/317.0fe7aa7f.js"><link rel="prefetch" href="/assets/js/318.bfe08f78.js"><link rel="prefetch" href="/assets/js/319.066bddbe.js"><link rel="prefetch" href="/assets/js/32.386fc03f.js"><link rel="prefetch" href="/assets/js/320.847e2d08.js"><link rel="prefetch" href="/assets/js/321.b352336f.js"><link rel="prefetch" href="/assets/js/322.603be18c.js"><link rel="prefetch" href="/assets/js/323.d5f6e667.js"><link rel="prefetch" href="/assets/js/324.ca18024b.js"><link rel="prefetch" href="/assets/js/325.6b1f9b6d.js"><link rel="prefetch" href="/assets/js/326.ea44500d.js"><link rel="prefetch" href="/assets/js/327.7bbcead6.js"><link rel="prefetch" href="/assets/js/328.c888f4f7.js"><link rel="prefetch" href="/assets/js/329.9ca35978.js"><link rel="prefetch" href="/assets/js/33.746055ec.js"><link rel="prefetch" href="/assets/js/330.57eaedf7.js"><link rel="prefetch" href="/assets/js/331.059af8f9.js"><link rel="prefetch" href="/assets/js/332.02bb2d02.js"><link rel="prefetch" href="/assets/js/333.b48bd3ca.js"><link rel="prefetch" href="/assets/js/334.214d40f6.js"><link rel="prefetch" href="/assets/js/335.737b8fc6.js"><link rel="prefetch" href="/assets/js/336.82c9bb00.js"><link rel="prefetch" href="/assets/js/337.b2130ccd.js"><link rel="prefetch" href="/assets/js/338.20e0b21e.js"><link rel="prefetch" href="/assets/js/339.7dadde3e.js"><link rel="prefetch" href="/assets/js/34.a590f0ae.js"><link rel="prefetch" href="/assets/js/340.75521c26.js"><link rel="prefetch" href="/assets/js/341.5e8dcd40.js"><link rel="prefetch" href="/assets/js/342.a5d2334a.js"><link rel="prefetch" href="/assets/js/343.4dfe4df5.js"><link rel="prefetch" href="/assets/js/344.51304626.js"><link rel="prefetch" href="/assets/js/345.36f7054e.js"><link rel="prefetch" href="/assets/js/346.cf308144.js"><link rel="prefetch" href="/assets/js/347.ef554007.js"><link rel="prefetch" href="/assets/js/348.99790f23.js"><link rel="prefetch" href="/assets/js/349.95f43e58.js"><link rel="prefetch" href="/assets/js/350.b5ea1eaa.js"><link rel="prefetch" href="/assets/js/351.89fa8c55.js"><link rel="prefetch" href="/assets/js/352.8c16b8ca.js"><link rel="prefetch" href="/assets/js/353.d21f105a.js"><link rel="prefetch" href="/assets/js/354.0aaddf4b.js"><link rel="prefetch" href="/assets/js/355.dd051989.js"><link rel="prefetch" href="/assets/js/356.faf1af8d.js"><link rel="prefetch" href="/assets/js/357.75c04705.js"><link rel="prefetch" href="/assets/js/358.ca3a90b8.js"><link rel="prefetch" href="/assets/js/359.855fba63.js"><link rel="prefetch" href="/assets/js/36.1b76e309.js"><link rel="prefetch" href="/assets/js/360.27218a17.js"><link rel="prefetch" href="/assets/js/361.effdafc4.js"><link rel="prefetch" href="/assets/js/362.ded22ed8.js"><link rel="prefetch" href="/assets/js/363.3470fd83.js"><link rel="prefetch" href="/assets/js/364.33cb94a1.js"><link rel="prefetch" href="/assets/js/365.4aeceb03.js"><link rel="prefetch" href="/assets/js/366.79ed763f.js"><link rel="prefetch" href="/assets/js/367.134d2beb.js"><link rel="prefetch" href="/assets/js/368.09c105ad.js"><link rel="prefetch" href="/assets/js/369.c292fc98.js"><link rel="prefetch" href="/assets/js/37.a06e01b7.js"><link rel="prefetch" href="/assets/js/370.d255386a.js"><link rel="prefetch" href="/assets/js/371.f4050548.js"><link rel="prefetch" href="/assets/js/372.1fdb1993.js"><link rel="prefetch" href="/assets/js/373.3d57762c.js"><link rel="prefetch" href="/assets/js/374.d1ccedfb.js"><link rel="prefetch" href="/assets/js/375.f9623d87.js"><link rel="prefetch" href="/assets/js/376.b35ee886.js"><link rel="prefetch" href="/assets/js/377.351393c2.js"><link rel="prefetch" href="/assets/js/378.abdf8b8c.js"><link rel="prefetch" href="/assets/js/379.84c2d7d5.js"><link rel="prefetch" href="/assets/js/38.9642b95b.js"><link rel="prefetch" href="/assets/js/380.9521cee5.js"><link rel="prefetch" href="/assets/js/381.fa77edfe.js"><link rel="prefetch" href="/assets/js/382.7fcaa731.js"><link rel="prefetch" href="/assets/js/383.1622cdc3.js"><link rel="prefetch" href="/assets/js/384.36db2c6e.js"><link rel="prefetch" href="/assets/js/385.4b730b34.js"><link rel="prefetch" href="/assets/js/386.c79395af.js"><link rel="prefetch" href="/assets/js/387.a4b0b0f9.js"><link rel="prefetch" href="/assets/js/388.ae2a8aeb.js"><link rel="prefetch" href="/assets/js/389.6c75c596.js"><link rel="prefetch" href="/assets/js/39.22df932f.js"><link rel="prefetch" href="/assets/js/390.270f48d0.js"><link rel="prefetch" href="/assets/js/391.4a8a9d82.js"><link rel="prefetch" href="/assets/js/392.7fe0d095.js"><link rel="prefetch" href="/assets/js/393.f1509b7e.js"><link rel="prefetch" href="/assets/js/394.21cd1b25.js"><link rel="prefetch" href="/assets/js/395.f2d42973.js"><link rel="prefetch" href="/assets/js/396.e5a103f4.js"><link rel="prefetch" href="/assets/js/397.8f1f4f18.js"><link rel="prefetch" href="/assets/js/398.45f67cf6.js"><link rel="prefetch" href="/assets/js/399.58b103d5.js"><link rel="prefetch" href="/assets/js/40.f10ebd42.js"><link rel="prefetch" href="/assets/js/400.7fca70bc.js"><link rel="prefetch" href="/assets/js/401.457e4e30.js"><link rel="prefetch" href="/assets/js/402.13d27406.js"><link rel="prefetch" href="/assets/js/403.28b9c70f.js"><link rel="prefetch" href="/assets/js/404.cbce41d9.js"><link rel="prefetch" href="/assets/js/405.cf33ac0b.js"><link rel="prefetch" href="/assets/js/406.e2735a9f.js"><link rel="prefetch" href="/assets/js/407.3f414c87.js"><link rel="prefetch" href="/assets/js/408.fb4c8562.js"><link rel="prefetch" href="/assets/js/409.20859a6a.js"><link rel="prefetch" href="/assets/js/41.c6ba31e8.js"><link rel="prefetch" href="/assets/js/410.e5b3a8b2.js"><link rel="prefetch" href="/assets/js/411.7c692a9f.js"><link rel="prefetch" href="/assets/js/412.ba646dd4.js"><link rel="prefetch" href="/assets/js/413.223b8db3.js"><link rel="prefetch" href="/assets/js/414.1b9eb6ed.js"><link rel="prefetch" href="/assets/js/415.e5e0c1f2.js"><link rel="prefetch" href="/assets/js/416.1a5511af.js"><link rel="prefetch" href="/assets/js/417.2157e276.js"><link rel="prefetch" href="/assets/js/418.31e27bc7.js"><link rel="prefetch" href="/assets/js/419.21185a8c.js"><link rel="prefetch" href="/assets/js/42.0bec1f12.js"><link rel="prefetch" href="/assets/js/420.e1bdae6b.js"><link rel="prefetch" href="/assets/js/421.d23db67d.js"><link rel="prefetch" href="/assets/js/422.863655c3.js"><link rel="prefetch" href="/assets/js/423.2331efd1.js"><link rel="prefetch" href="/assets/js/424.c49bf601.js"><link rel="prefetch" href="/assets/js/425.57b9fa7a.js"><link rel="prefetch" href="/assets/js/426.06be7ab4.js"><link rel="prefetch" href="/assets/js/427.3d3d3823.js"><link rel="prefetch" href="/assets/js/428.41c85071.js"><link rel="prefetch" href="/assets/js/429.5fe617b2.js"><link rel="prefetch" href="/assets/js/43.4193f196.js"><link rel="prefetch" href="/assets/js/430.d133d3b6.js"><link rel="prefetch" href="/assets/js/431.902d4b9c.js"><link rel="prefetch" href="/assets/js/432.a19c1786.js"><link rel="prefetch" href="/assets/js/433.3266bbe4.js"><link rel="prefetch" href="/assets/js/434.65d855ed.js"><link rel="prefetch" href="/assets/js/435.14b85953.js"><link rel="prefetch" href="/assets/js/436.106d5e31.js"><link rel="prefetch" href="/assets/js/437.a1bc9b09.js"><link rel="prefetch" href="/assets/js/438.6a91ec48.js"><link rel="prefetch" href="/assets/js/439.0b848bcd.js"><link rel="prefetch" href="/assets/js/44.0e2c101c.js"><link rel="prefetch" href="/assets/js/440.71b9a612.js"><link rel="prefetch" href="/assets/js/441.27d36f94.js"><link rel="prefetch" href="/assets/js/442.2b200a2e.js"><link rel="prefetch" href="/assets/js/443.c113db42.js"><link rel="prefetch" href="/assets/js/444.8a821b02.js"><link rel="prefetch" href="/assets/js/445.69e776af.js"><link rel="prefetch" href="/assets/js/446.9424c2d8.js"><link rel="prefetch" href="/assets/js/447.93003309.js"><link rel="prefetch" href="/assets/js/448.68647159.js"><link rel="prefetch" href="/assets/js/449.4e699a36.js"><link rel="prefetch" href="/assets/js/45.906f0670.js"><link rel="prefetch" href="/assets/js/450.0c436dbd.js"><link rel="prefetch" href="/assets/js/451.e3703771.js"><link rel="prefetch" href="/assets/js/452.bcda8552.js"><link rel="prefetch" href="/assets/js/453.e8bf8887.js"><link rel="prefetch" href="/assets/js/454.cfad4fae.js"><link rel="prefetch" href="/assets/js/455.f8bda945.js"><link rel="prefetch" href="/assets/js/456.9260cf29.js"><link rel="prefetch" href="/assets/js/457.96ab8141.js"><link rel="prefetch" href="/assets/js/458.14de9202.js"><link rel="prefetch" href="/assets/js/459.ee0d815f.js"><link rel="prefetch" href="/assets/js/46.1d25bb03.js"><link rel="prefetch" href="/assets/js/460.e4457a3e.js"><link rel="prefetch" href="/assets/js/461.4e20b7b5.js"><link rel="prefetch" href="/assets/js/462.f4bf43ba.js"><link rel="prefetch" href="/assets/js/463.0748a80e.js"><link rel="prefetch" href="/assets/js/464.53a27dd7.js"><link rel="prefetch" href="/assets/js/465.a4acd1af.js"><link rel="prefetch" href="/assets/js/466.df090992.js"><link rel="prefetch" href="/assets/js/467.b16a86c8.js"><link rel="prefetch" href="/assets/js/468.6a2925c4.js"><link rel="prefetch" href="/assets/js/469.bde97422.js"><link rel="prefetch" href="/assets/js/47.b4abc3a9.js"><link rel="prefetch" href="/assets/js/470.c098e3ca.js"><link rel="prefetch" href="/assets/js/471.b514ba1c.js"><link rel="prefetch" href="/assets/js/472.c0a5029e.js"><link rel="prefetch" href="/assets/js/473.0816d6de.js"><link rel="prefetch" href="/assets/js/474.dca423db.js"><link rel="prefetch" href="/assets/js/475.0cd7d27f.js"><link rel="prefetch" href="/assets/js/476.671f7b2c.js"><link rel="prefetch" href="/assets/js/477.5afec85f.js"><link rel="prefetch" href="/assets/js/478.456ee291.js"><link rel="prefetch" href="/assets/js/479.ec486138.js"><link rel="prefetch" href="/assets/js/48.d5735fb1.js"><link rel="prefetch" href="/assets/js/480.515ff69b.js"><link rel="prefetch" href="/assets/js/481.f3819ec2.js"><link rel="prefetch" href="/assets/js/482.54aa04d1.js"><link rel="prefetch" href="/assets/js/483.398fde55.js"><link rel="prefetch" href="/assets/js/484.95f23223.js"><link rel="prefetch" href="/assets/js/485.63ffa136.js"><link rel="prefetch" href="/assets/js/486.c76fb274.js"><link rel="prefetch" href="/assets/js/487.2733991b.js"><link rel="prefetch" href="/assets/js/488.d24d37c4.js"><link rel="prefetch" href="/assets/js/489.ad6ad8cb.js"><link rel="prefetch" href="/assets/js/49.f041ca9b.js"><link rel="prefetch" href="/assets/js/490.3720e59a.js"><link rel="prefetch" href="/assets/js/491.e8277c13.js"><link rel="prefetch" href="/assets/js/492.0b099660.js"><link rel="prefetch" href="/assets/js/493.aed218e9.js"><link rel="prefetch" href="/assets/js/494.d1c9814e.js"><link rel="prefetch" href="/assets/js/495.c40e5c0d.js"><link rel="prefetch" href="/assets/js/496.e8d0ddbd.js"><link rel="prefetch" href="/assets/js/497.1025ce49.js"><link rel="prefetch" href="/assets/js/498.8685a6f8.js"><link rel="prefetch" href="/assets/js/499.387e4c41.js"><link rel="prefetch" href="/assets/js/5.eace4687.js"><link rel="prefetch" href="/assets/js/50.d5f95b25.js"><link rel="prefetch" href="/assets/js/500.c3d3f23c.js"><link rel="prefetch" href="/assets/js/501.40523dbb.js"><link rel="prefetch" href="/assets/js/502.e0c00888.js"><link rel="prefetch" href="/assets/js/503.073cc6ef.js"><link rel="prefetch" href="/assets/js/504.21612170.js"><link rel="prefetch" href="/assets/js/505.2b31e14b.js"><link rel="prefetch" href="/assets/js/506.03bd71db.js"><link rel="prefetch" href="/assets/js/507.08ef2c8a.js"><link rel="prefetch" href="/assets/js/508.9639ee84.js"><link rel="prefetch" href="/assets/js/509.51737525.js"><link rel="prefetch" href="/assets/js/51.d15e6446.js"><link rel="prefetch" href="/assets/js/510.2502897d.js"><link rel="prefetch" href="/assets/js/511.89d2c25e.js"><link rel="prefetch" href="/assets/js/512.f4dcd865.js"><link rel="prefetch" href="/assets/js/513.794fa087.js"><link rel="prefetch" href="/assets/js/514.9fe28740.js"><link rel="prefetch" href="/assets/js/515.9058554f.js"><link rel="prefetch" href="/assets/js/516.407c9790.js"><link rel="prefetch" href="/assets/js/517.85975bd0.js"><link rel="prefetch" href="/assets/js/518.00e4e242.js"><link rel="prefetch" href="/assets/js/519.f8a22cbe.js"><link rel="prefetch" href="/assets/js/52.b00654a7.js"><link rel="prefetch" href="/assets/js/520.33769056.js"><link rel="prefetch" href="/assets/js/521.0e1fa632.js"><link rel="prefetch" href="/assets/js/522.6134619e.js"><link rel="prefetch" href="/assets/js/523.5da64aae.js"><link rel="prefetch" href="/assets/js/524.e7b954d0.js"><link rel="prefetch" href="/assets/js/525.7a412451.js"><link rel="prefetch" href="/assets/js/526.5d12978f.js"><link rel="prefetch" href="/assets/js/527.73533cb0.js"><link rel="prefetch" href="/assets/js/528.8b0d61e1.js"><link rel="prefetch" href="/assets/js/529.566e828d.js"><link rel="prefetch" href="/assets/js/53.355eef4b.js"><link rel="prefetch" href="/assets/js/530.3a222133.js"><link rel="prefetch" href="/assets/js/531.f5e2b851.js"><link rel="prefetch" href="/assets/js/532.edaa8a87.js"><link rel="prefetch" href="/assets/js/533.2daeb978.js"><link rel="prefetch" href="/assets/js/534.9d47f4a6.js"><link rel="prefetch" href="/assets/js/535.eb0ce578.js"><link rel="prefetch" href="/assets/js/536.4e9ed498.js"><link rel="prefetch" href="/assets/js/537.708f6016.js"><link rel="prefetch" href="/assets/js/538.21a9740f.js"><link rel="prefetch" href="/assets/js/539.79842b7b.js"><link rel="prefetch" href="/assets/js/54.ae51d1f6.js"><link rel="prefetch" href="/assets/js/540.b5628db5.js"><link rel="prefetch" href="/assets/js/541.cc3c7bf3.js"><link rel="prefetch" href="/assets/js/542.308706eb.js"><link rel="prefetch" href="/assets/js/543.c62fa106.js"><link rel="prefetch" href="/assets/js/544.4328c991.js"><link rel="prefetch" href="/assets/js/545.48999b2a.js"><link rel="prefetch" href="/assets/js/546.f1f8da57.js"><link rel="prefetch" href="/assets/js/547.7b43a913.js"><link rel="prefetch" href="/assets/js/548.1c459864.js"><link rel="prefetch" href="/assets/js/549.c052439d.js"><link rel="prefetch" href="/assets/js/55.cd2a5a2e.js"><link rel="prefetch" href="/assets/js/550.331dd311.js"><link rel="prefetch" href="/assets/js/551.a52cce71.js"><link rel="prefetch" href="/assets/js/552.e2dbac7d.js"><link rel="prefetch" href="/assets/js/553.8bc4e621.js"><link rel="prefetch" href="/assets/js/554.be5b47c5.js"><link rel="prefetch" href="/assets/js/555.f73c61d3.js"><link rel="prefetch" href="/assets/js/556.e721d3d8.js"><link rel="prefetch" href="/assets/js/557.cbb48495.js"><link rel="prefetch" href="/assets/js/558.ec48dcb9.js"><link rel="prefetch" href="/assets/js/559.d68e0c89.js"><link rel="prefetch" href="/assets/js/56.3972fd13.js"><link rel="prefetch" href="/assets/js/560.ca66ac86.js"><link rel="prefetch" href="/assets/js/561.2722f881.js"><link rel="prefetch" href="/assets/js/562.5be8d211.js"><link rel="prefetch" href="/assets/js/563.52d710f5.js"><link rel="prefetch" href="/assets/js/564.f94bb0bd.js"><link rel="prefetch" href="/assets/js/565.32642e9c.js"><link rel="prefetch" href="/assets/js/566.e4996ba1.js"><link rel="prefetch" href="/assets/js/567.807b6f65.js"><link rel="prefetch" href="/assets/js/568.39395163.js"><link rel="prefetch" href="/assets/js/569.ce6d29a6.js"><link rel="prefetch" href="/assets/js/57.0e1aed8c.js"><link rel="prefetch" href="/assets/js/570.5eaff1de.js"><link rel="prefetch" href="/assets/js/571.3ddce2bd.js"><link rel="prefetch" href="/assets/js/572.5f9a6d45.js"><link rel="prefetch" href="/assets/js/573.16834fb7.js"><link rel="prefetch" href="/assets/js/574.0742d701.js"><link rel="prefetch" href="/assets/js/575.b5ae9dd1.js"><link rel="prefetch" href="/assets/js/576.abe5b760.js"><link rel="prefetch" href="/assets/js/577.68ce8edd.js"><link rel="prefetch" href="/assets/js/578.2a48109d.js"><link rel="prefetch" href="/assets/js/579.cb1a78e4.js"><link rel="prefetch" href="/assets/js/58.e5669615.js"><link rel="prefetch" href="/assets/js/580.bf701d4d.js"><link rel="prefetch" href="/assets/js/581.47cbc0d4.js"><link rel="prefetch" href="/assets/js/582.494a2d92.js"><link rel="prefetch" href="/assets/js/583.fb8a687c.js"><link rel="prefetch" href="/assets/js/584.db6f15b5.js"><link rel="prefetch" href="/assets/js/585.5ea6b3e5.js"><link rel="prefetch" href="/assets/js/586.ab5ce50c.js"><link rel="prefetch" href="/assets/js/587.f5f33272.js"><link rel="prefetch" href="/assets/js/588.c1466d25.js"><link rel="prefetch" href="/assets/js/589.df2c521f.js"><link rel="prefetch" href="/assets/js/59.299b0b27.js"><link rel="prefetch" href="/assets/js/590.8fde4565.js"><link rel="prefetch" href="/assets/js/591.ebae3557.js"><link rel="prefetch" href="/assets/js/592.dce57142.js"><link rel="prefetch" href="/assets/js/593.ea31c530.js"><link rel="prefetch" href="/assets/js/594.75078d8e.js"><link rel="prefetch" href="/assets/js/595.91c91388.js"><link rel="prefetch" href="/assets/js/596.f647f12f.js"><link rel="prefetch" href="/assets/js/597.98c3fe10.js"><link rel="prefetch" href="/assets/js/598.0a0bfe0d.js"><link rel="prefetch" href="/assets/js/599.11927d65.js"><link rel="prefetch" href="/assets/js/6.008dd0d6.js"><link rel="prefetch" href="/assets/js/60.7a3eb10d.js"><link rel="prefetch" href="/assets/js/600.599af816.js"><link rel="prefetch" href="/assets/js/601.e05e001b.js"><link rel="prefetch" href="/assets/js/602.4574a400.js"><link rel="prefetch" href="/assets/js/603.f25f60f9.js"><link rel="prefetch" href="/assets/js/604.432b0d89.js"><link rel="prefetch" href="/assets/js/605.97635503.js"><link rel="prefetch" href="/assets/js/606.099c5cc0.js"><link rel="prefetch" href="/assets/js/607.f373dc6f.js"><link rel="prefetch" href="/assets/js/608.9a97fb61.js"><link rel="prefetch" href="/assets/js/609.d644e9f4.js"><link rel="prefetch" href="/assets/js/61.97cd71d2.js"><link rel="prefetch" href="/assets/js/610.ef6f5b50.js"><link rel="prefetch" href="/assets/js/611.fc56c15a.js"><link rel="prefetch" href="/assets/js/612.6c18ff9d.js"><link rel="prefetch" href="/assets/js/613.454523c0.js"><link rel="prefetch" href="/assets/js/614.b99e3acf.js"><link rel="prefetch" href="/assets/js/615.c3fa6c17.js"><link rel="prefetch" href="/assets/js/616.3c376364.js"><link rel="prefetch" href="/assets/js/617.eb95de76.js"><link rel="prefetch" href="/assets/js/618.05e65c70.js"><link rel="prefetch" href="/assets/js/619.1e3bb7bc.js"><link rel="prefetch" href="/assets/js/62.309d2360.js"><link rel="prefetch" href="/assets/js/620.2a493bee.js"><link rel="prefetch" href="/assets/js/621.94f87c1f.js"><link rel="prefetch" href="/assets/js/622.7ae48b4b.js"><link rel="prefetch" href="/assets/js/623.3c371fca.js"><link rel="prefetch" href="/assets/js/624.3baafe90.js"><link rel="prefetch" href="/assets/js/625.5912d2e7.js"><link rel="prefetch" href="/assets/js/626.6821148e.js"><link rel="prefetch" href="/assets/js/627.5823614e.js"><link rel="prefetch" href="/assets/js/628.70d87f62.js"><link rel="prefetch" href="/assets/js/629.ff8d8723.js"><link rel="prefetch" href="/assets/js/63.72ce087d.js"><link rel="prefetch" href="/assets/js/630.9e2ed4f7.js"><link rel="prefetch" href="/assets/js/631.b311c084.js"><link rel="prefetch" href="/assets/js/632.f5887044.js"><link rel="prefetch" href="/assets/js/633.5cfd40ff.js"><link rel="prefetch" href="/assets/js/634.4d1e475f.js"><link rel="prefetch" href="/assets/js/635.ec46017b.js"><link rel="prefetch" href="/assets/js/636.16f35f64.js"><link rel="prefetch" href="/assets/js/637.f3886ccd.js"><link rel="prefetch" href="/assets/js/638.3adc73a1.js"><link rel="prefetch" href="/assets/js/639.2e685514.js"><link rel="prefetch" href="/assets/js/64.002a0314.js"><link rel="prefetch" href="/assets/js/640.311cc5d7.js"><link rel="prefetch" href="/assets/js/641.2682e9c4.js"><link rel="prefetch" href="/assets/js/642.b476da53.js"><link rel="prefetch" href="/assets/js/643.aac8e411.js"><link rel="prefetch" href="/assets/js/644.4f4ac975.js"><link rel="prefetch" href="/assets/js/645.7636ef74.js"><link rel="prefetch" href="/assets/js/646.456054a7.js"><link rel="prefetch" href="/assets/js/647.e278e376.js"><link rel="prefetch" href="/assets/js/648.0ed73224.js"><link rel="prefetch" href="/assets/js/649.5d7983af.js"><link rel="prefetch" href="/assets/js/65.ceafbc3b.js"><link rel="prefetch" href="/assets/js/66.cf550ed0.js"><link rel="prefetch" href="/assets/js/67.fbb16acb.js"><link rel="prefetch" href="/assets/js/68.795e44e8.js"><link rel="prefetch" href="/assets/js/69.7c79f101.js"><link rel="prefetch" href="/assets/js/7.080f75db.js"><link rel="prefetch" href="/assets/js/70.47360ac4.js"><link rel="prefetch" href="/assets/js/71.5297f175.js"><link rel="prefetch" href="/assets/js/72.6dd2294f.js"><link rel="prefetch" href="/assets/js/73.ccaf19fe.js"><link rel="prefetch" href="/assets/js/74.6765e270.js"><link rel="prefetch" href="/assets/js/75.faae1b37.js"><link rel="prefetch" href="/assets/js/76.184c6746.js"><link rel="prefetch" href="/assets/js/77.53e2f632.js"><link rel="prefetch" href="/assets/js/78.acc96819.js"><link rel="prefetch" href="/assets/js/79.3394bd3a.js"><link rel="prefetch" href="/assets/js/8.d214e90e.js"><link rel="prefetch" href="/assets/js/80.c1c43c7e.js"><link rel="prefetch" href="/assets/js/81.3517c2a2.js"><link rel="prefetch" href="/assets/js/82.2f67198d.js"><link rel="prefetch" href="/assets/js/83.20200195.js"><link rel="prefetch" href="/assets/js/84.8b852a85.js"><link rel="prefetch" href="/assets/js/85.9f4cf1b7.js"><link rel="prefetch" href="/assets/js/86.5dfb2da0.js"><link rel="prefetch" href="/assets/js/87.fd79b5e1.js"><link rel="prefetch" href="/assets/js/88.a9577c73.js"><link rel="prefetch" href="/assets/js/89.de6dd42f.js"><link rel="prefetch" href="/assets/js/9.15e59c54.js"><link rel="prefetch" href="/assets/js/90.ef78cdaf.js"><link rel="prefetch" href="/assets/js/91.82080b50.js"><link rel="prefetch" href="/assets/js/92.a2ebe8f3.js"><link rel="prefetch" href="/assets/js/93.0619a7be.js"><link rel="prefetch" href="/assets/js/94.c068c916.js"><link rel="prefetch" href="/assets/js/95.5d813553.js"><link rel="prefetch" href="/assets/js/96.49162df6.js"><link rel="prefetch" href="/assets/js/97.e49a092b.js"><link rel="prefetch" href="/assets/js/98.7d52bcd6.js"><link rel="prefetch" href="/assets/js/99.566e149b.js"><link rel="prefetch" href="/assets/js/vendors~docsearch.1288603f.js">
    <link rel="stylesheet" href="/assets/css/0.styles.c79f5191.css">
  </head>
  <body>
    <div id="app" data-server-rendered="true"><div class="theme-container"><header class="navbar"><div class="sidebar-button"><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" role="img" viewBox="0 0 448 512" class="icon"><path fill="currentColor" d="M436 124H12c-6.627 0-12-5.373-12-12V80c0-6.627 5.373-12 12-12h424c6.627 0 12 5.373 12 12v32c0 6.627-5.373 12-12 12zm0 160H12c-6.627 0-12-5.373-12-12v-32c0-6.627 5.373-12 12-12h424c6.627 0 12 5.373 12 12v32c0 6.627-5.373 12-12 12zm0 160H12c-6.627 0-12-5.373-12-12v-32c0-6.627 5.373-12 12-12h424c6.627 0 12 5.373 12 12v32c0 6.627-5.373 12-12 12z"></path></svg></div> <a href="/" class="home-link router-link-active"><img src="/img/logo.png" alt=" " class="logo"></a> <div class="links"><div class="search-box"><input aria-label="Search" autocomplete="off" spellcheck="false" value=""> <!----></div> <nav class="nav-links can-hide"><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Document</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/UserGuide/Master/QuickStart/QuickStart.html" class="nav-link">In progress</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.12.x/QuickStart/QuickStart.html" class="nav-link">V0.12.x</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.11.x/Get Started/QuickStart.html" class="nav-link">V0.11.x</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.10.x/Get Started/QuickStart.html" class="nav-link">V0.10.x</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.9.x/0-Get Started/1-QuickStart.html" class="nav-link">V0.9.x</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.8.x/0-Get Started/1-QuickStart.html" class="nav-link">V0.8.x</a></li></ul></div></div><div class="nav-item"><a href="/SystemDesign/Architecture/Architecture.html" class="nav-link">System design</a></div><div class="nav-item"><a href="/Download/" class="nav-link">Download</a></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Community</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="https://cwiki.apache.org/confluence/display/iotdb" class="nav-link external">
  Wiki
  <!----></a></li><li class="dropdown-item"><!----> <a href="/Community/Community-Project Committers.html" class="nav-link">People</a></li><li class="dropdown-item"><!----> <a href="/Community/Community-Powered By.html" class="nav-link">Powered By</a></li><li class="dropdown-item"><!----> <a href="/Community/Materials.html" class="nav-link">Resources</a></li><li class="dropdown-item"><!----> <a href="/Community/Feedback.html" class="nav-link">Feedback</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Development</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/Development/VoteRelease.html" class="nav-link">How to vote</a></li><li class="dropdown-item"><!----> <a href="/Development/HowToCommit.html" class="nav-link">How to Commit</a></li><li class="dropdown-item"><!----> <a href="/Development/Committer.html" class="nav-link">Become a Committer</a></li><li class="dropdown-item"><!----> <a href="/Development/ContributeGuide.html" class="nav-link">ContributeGuide</a></li><li class="dropdown-item"><!----> <a href="/Development/format-changelist.html" class="nav-link">Changelist of TsFile</a></li><li class="dropdown-item"><!----> <a href="/Development/rpc-changelist.html" class="nav-link">Changelist of RPC</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Blog</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/Blog/Index.html" class="nav-link">Overview</a></li><li class="dropdown-item"><!----> <a href="/Blog/Release0_93.html" class="nav-link">Some Notes on Release 0.9.3 and upcoming 0.10.0</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">ASF</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="http://www.apache.org/" class="nav-link external">
  Foundation
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/licenses/" class="nav-link external">
  License
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/security/" class="nav-link external">
  Security
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/foundation/sponsorship.html" class="nav-link external">
  Sponsorship
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/foundation/thanks.html" class="nav-link external">
  Thanks
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/events/current-event" class="nav-link external">
  Current Events
  <!----></a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Languages</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/SystemDesign/DataQuery/GroupByFillQuery.html" aria-current="page" class="nav-link router-link-exact-active router-link-active">English</a></li><li class="dropdown-item"><!----> <a href="/zh/SystemDesign/DataQuery/GroupByFillQuery.html" class="nav-link">简体中文</a></li></ul></div></div> <a href="https://github.com/apache/iotdb.git" target="_blank" rel="noopener noreferrer" class="repo-link">
    gitHub
    <span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a></nav></div></header> <div class="sidebar-mask"></div> <aside class="sidebar"><nav class="nav-links"><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Document</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/UserGuide/Master/QuickStart/QuickStart.html" class="nav-link">In progress</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.12.x/QuickStart/QuickStart.html" class="nav-link">V0.12.x</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.11.x/Get Started/QuickStart.html" class="nav-link">V0.11.x</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.10.x/Get Started/QuickStart.html" class="nav-link">V0.10.x</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.9.x/0-Get Started/1-QuickStart.html" class="nav-link">V0.9.x</a></li><li class="dropdown-item"><!----> <a href="/UserGuide/V0.8.x/0-Get Started/1-QuickStart.html" class="nav-link">V0.8.x</a></li></ul></div></div><div class="nav-item"><a href="/SystemDesign/Architecture/Architecture.html" class="nav-link">System design</a></div><div class="nav-item"><a href="/Download/" class="nav-link">Download</a></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Community</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="https://cwiki.apache.org/confluence/display/iotdb" class="nav-link external">
  Wiki
  <!----></a></li><li class="dropdown-item"><!----> <a href="/Community/Community-Project Committers.html" class="nav-link">People</a></li><li class="dropdown-item"><!----> <a href="/Community/Community-Powered By.html" class="nav-link">Powered By</a></li><li class="dropdown-item"><!----> <a href="/Community/Materials.html" class="nav-link">Resources</a></li><li class="dropdown-item"><!----> <a href="/Community/Feedback.html" class="nav-link">Feedback</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Development</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/Development/VoteRelease.html" class="nav-link">How to vote</a></li><li class="dropdown-item"><!----> <a href="/Development/HowToCommit.html" class="nav-link">How to Commit</a></li><li class="dropdown-item"><!----> <a href="/Development/Committer.html" class="nav-link">Become a Committer</a></li><li class="dropdown-item"><!----> <a href="/Development/ContributeGuide.html" class="nav-link">ContributeGuide</a></li><li class="dropdown-item"><!----> <a href="/Development/format-changelist.html" class="nav-link">Changelist of TsFile</a></li><li class="dropdown-item"><!----> <a href="/Development/rpc-changelist.html" class="nav-link">Changelist of RPC</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Blog</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/Blog/Index.html" class="nav-link">Overview</a></li><li class="dropdown-item"><!----> <a href="/Blog/Release0_93.html" class="nav-link">Some Notes on Release 0.9.3 and upcoming 0.10.0</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">ASF</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="http://www.apache.org/" class="nav-link external">
  Foundation
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/licenses/" class="nav-link external">
  License
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/security/" class="nav-link external">
  Security
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/foundation/sponsorship.html" class="nav-link external">
  Sponsorship
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/foundation/thanks.html" class="nav-link external">
  Thanks
  <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/events/current-event" class="nav-link external">
  Current Events
  <!----></a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">Languages</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/SystemDesign/DataQuery/GroupByFillQuery.html" aria-current="page" class="nav-link router-link-exact-active router-link-active">English</a></li><li class="dropdown-item"><!----> <a href="/zh/SystemDesign/DataQuery/GroupByFillQuery.html" class="nav-link">简体中文</a></li></ul></div></div> <a href="https://github.com/apache/iotdb.git" target="_blank" rel="noopener noreferrer" class="repo-link">
    gitHub
    <span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a></nav>  <ul class="sidebar-links"><li><section class="sidebar-group depth-0"><p class="sidebar-heading"><span>System design</span> <!----></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>Architecture</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>TsFile</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>QueryEngine</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>SchemaManager</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>StorageEngine</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading open"><span>DataQuery</span> <span class="arrow down"></span></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/SystemDesign/DataQuery/DataQuery.html" class="sidebar-link">DataQuery</a></li><li><a href="/SystemDesign/DataQuery/QueryFundamentals.html" class="sidebar-link">QueryFundamentals</a></li><li><a href="/SystemDesign/DataQuery/SeriesReader.html" class="sidebar-link">SeriesReader</a></li><li><a href="/SystemDesign/DataQuery/RawDataQuery.html" class="sidebar-link">RawDataQuery</a></li><li><a href="/SystemDesign/DataQuery/AggregationQuery.html" class="sidebar-link">AggregationQuery</a></li><li><a href="/SystemDesign/DataQuery/GroupByQuery.html" class="sidebar-link">GroupByQuery</a></li><li><a href="/SystemDesign/DataQuery/LastQuery.html" class="sidebar-link">LastQuery</a></li><li><a href="/SystemDesign/DataQuery/AlignByDeviceQuery.html" class="sidebar-link">AlignByDeviceQuery</a></li><li><a href="/SystemDesign/DataQuery/FillFunction.html" class="sidebar-link">FillFunction</a></li><li><a href="/SystemDesign/DataQuery/GroupByFillQuery.html" aria-current="page" class="active sidebar-link">GroupByFillQuery</a></li></ul></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>Tools</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>Connector</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>Client</span> <span class="arrow right"></span></p> <!----></section></li></ul> </aside> <main class="page"> <div class="content content__default"><h1 id="group-by-fill"><a href="#group-by-fill" class="header-anchor">#</a> Group by fill</h1> <p>The main logic of GroupByFill query is in <code>GroupByFillDataSet</code></p> <ul><li><code>org.apache.iotdb.db.query.dataset.groupby.GroupByFillDataSet</code></li></ul> <p>GroupByFill is used to fill the null value of the group by result.</p> <p>Note that:</p> <ul><li>In group by fill, sliding step is not supported in group by clause</li> <li>Now, only last_value aggregation function is supported in group by fill.</li> <li>Linear fill is not supported in group by fill.</li></ul> <h2 id="difference-between-previousuntillast-fill-and-previous-fill"><a href="#difference-between-previousuntillast-fill-and-previous-fill" class="header-anchor">#</a> Difference between PREVIOUSUNTILLAST fill and PREVIOUS fill</h2> <p>PREVIOUS will fill every interval generated from group by if possible, However, PREVIOUSUNTILLAST will just fill until the last time of the specified time series and the interval after the last time won't be filled and will be null.</p> <p>Here is an example:</p> <p>Timestamp of point A is 1, point B is 5, point C is 20, point D is 30, point N is 8 and point M is 38.</p> <p>Raw Data is like:
<img src="https://user-images.githubusercontent.com/16079446/78784824-9f41ae00-79d8-11ea-9920-0825e081cae0.png" style="width:100%;max-width:800px;max-height:600px;margin-left:auto;margin-right:auto;display:block;"></p> <p><code>select temperature FROM root.ln.wf01.wt01 where time &gt;= 1 and time &lt;= 38</code></p> <table><thead><tr><th>Time</th> <th>root.ln.wf01.wt01.temperature</th></tr></thead> <tbody><tr><td>1</td> <td>21</td></tr> <tr><td>3</td> <td>23</td></tr> <tr><td>5</td> <td>25</td></tr> <tr><td>20</td> <td>26</td></tr> <tr><td>27</td> <td>29</td></tr> <tr><td>28</td> <td>30</td></tr> <tr><td>30</td> <td>40</td></tr></tbody></table> <p>When we use Previous fill, even though the data between D and M is from the future, we should also use value of point D to fill them.</p> <p><code>SELECT last_value(temperature) as last_temperature FROM root.ln.wf01.wt01 GROUP BY([8, 39), 5m) FILL (int32[previous])</code></p> <table><thead><tr><th>Time</th> <th>last_temperature</th></tr></thead> <tbody><tr><td>8</td> <td>25</td></tr> <tr><td>13</td> <td>25</td></tr> <tr><td>18</td> <td>26</td></tr> <tr><td>23</td> <td>29</td></tr> <tr><td>28</td> <td>40</td></tr> <tr><td>33</td> <td>40</td></tr> <tr><td>38</td> <td>40</td></tr></tbody></table> <p>However, When we use NONLASTPREVIOUS fill, because data between D and M is from the future, we won't fill them and still return null.</p> <p><code>SELECT last_value(temperature) as last_temperature FROM root.ln.wf01.wt01 GROUP BY([8, 39), 5m) FILL (int32[PREVIOUSUNTILLAST])</code></p> <table><thead><tr><th>Time</th> <th>last_temperature</th></tr></thead> <tbody><tr><td>8</td> <td>25</td></tr> <tr><td>13</td> <td>25</td></tr> <tr><td>18</td> <td>26</td></tr> <tr><td>23</td> <td>29</td></tr> <tr><td>28</td> <td>40</td></tr> <tr><td>33</td> <td>null</td></tr> <tr><td>38</td> <td>null</td></tr></tbody></table> <h2 id="core-query-logic"><a href="#core-query-logic" class="header-anchor">#</a> Core query logic</h2> <p>We maintain two primary variable in <code>GroupByFillDataSet</code></p> <div class="language- line-numbers-mode"><pre class="language-text"><code>// the first value for each time series
private Object[] previousValue;
// last timestamp for each time series
private long[] lastTimeArray;
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br></div></div><h3 id="previousvalue"><a href="#previousvalue" class="header-anchor">#</a> <code>previousValue</code></h3> <p><code>previousValue</code> maintain the previous value before current time interval for each time series and we initialize it by calling the <code>initPreviousParis</code> method in the constructor of <code>GroupByFillDataSet</code>.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>  private void initPreviousParis(QueryContext context, GroupByFillPlan groupByFillPlan)
          throws StorageEngineException, IOException, QueryProcessException {
    previousValue = new Object[paths.size()];
    for (int i = 0; i &lt; paths.size(); i++) {
      Path path = paths.get(i);
      TSDataType dataType = dataTypes.get(i);
      IFill fill = new PreviousFill(dataType, groupByEngineDataSet.getStartTime(), -1L);
      fill.constructReaders(path, groupByFillPlan.getAllMeasurementsInDevice(path.getDevice()), context);

      TimeValuePair timeValuePair = fill.getFillResult();
      if (timeValuePair == null || timeValuePair.getValue() == null) {
        previousValue[i] = null;
      } else {
        previousValue[i] = timeValuePair.getValue().getValue();
      }
    }
  }
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br></div></div><p><code>initPreviousParis</code> construct a Single point supplementary null query for each time series and the parameter <code>queryTime</code> is set to the start time of group by query and the parameter <code>beforeRange</code> is set to -1.</p> <h3 id="lasttimearray"><a href="#lasttimearray" class="header-anchor">#</a> <code>lastTimeArray</code></h3> <p><code>lastTimeArray</code> maintain the last timestamp for each time series and is used in PREVIOUSUNTILLAST fill way. initialize it by calling the <code>initLastTimeArray</code> method in the constructor of <code>GroupByFillDataSet</code>.</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>  private void initLastTimeArray(QueryContext context)
      throws IOException, StorageEngineException, QueryProcessException {
    lastTimeArray = new long[paths.size()];
    Arrays.fill(lastTimeArray, Long.MAX_VALUE);
    for (int i = 0; i &lt; paths.size(); i++) {
      TimeValuePair lastTimeValuePair =
          LastQueryExecutor.calculateLastPairForOneSeries(paths.get(i), dataTypes.get(i), context);
      if (lastTimeValuePair.getValue() != null) {
        lastTimeArray[i] = lastTimeValuePair.getTimestamp();
      }
    }
  }
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br></div></div><p><code>initPreviousParis</code> construct a last query for each time series.</p> <h3 id="the-process-of-filling"><a href="#the-process-of-filling" class="header-anchor">#</a> The process of filling</h3> <p>The logic of filling is in the <code>nextWithoutConstraint</code> method:</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>protected RowRecord nextWithoutConstraint() throws IOException {

    // get group by result without filling through groupByEngineDataSet
    RowRecord rowRecord = groupByEngineDataSet.nextWithoutConstraint();

    // judge whether each time series is needed to be filled
    for (int i = 0; i &lt; paths.size(); i++) {
      Field field = rowRecord.getFields().get(i);
      // current group by result is null
      if (field.getDataType() == null) {
        // the previous value is not null and (fill type is not previous until last or now time is before last time)
        if (previousValue[i] != null
            &amp;&amp; (!((PreviousFill) fillTypes.get(dataTypes.get(i))).isUntilLast()
            || rowRecord.getTimestamp() &lt;= lastTimeArray[i])) {
          rowRecord.getFields().set(i, Field.getField(previousValue[i], dataTypes.get(i)));
        }
      } else {
        // current group by result is not null，no need to fill
        // use now value update previous value
        previousValue[i] = field.getObjectValue(field.getDataType());
      }
    }
    return rowRecord;
  }
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br></div></div></div> <div class="page-nav"><p class="inner"><span class="prev">
        ←
        <a href="/SystemDesign/DataQuery/FillFunction.html" class="prev">
          FillFunction
        </a></span> <span class="next"><a href="/SystemDesign/Tools/Sync.html">
          Sync
        </a>
        →
      </span></p></div> <p style="text-align: center;">Copyright © 2021 The Apache Software Foundation.<br>
     Apache and the Apache feather logo are trademarks of The Apache Software Foundation</p> <p style="text-align: center; margin-top: 10px; color: #444">
    Contact us: Join QQ Group 659990460 | Add friend <i>tietouqiao</i> and be invited to Wechat Group<br>
    see <a href="https://github.com/apache/iotdb/issues/1995">Join the community</a> for more</p></main></div><div class="global-ui"></div></div>
    <script src="/assets/js/app.150a3d30.js" defer></script><script src="/assets/js/3.96a076a8.js" defer></script><script src="/assets/js/4.a65360c5.js" defer></script><script src="/assets/js/35.135cd75d.js" defer></script>
  </body>
</html>