| <!DOCTYPE html> |
| <html lang="zh-CN"> |
| <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.ccadf850.css" as="style"><link rel="preload" href="/assets/js/app.821c382f.js" as="script"><link rel="preload" href="/assets/js/3.5626571b.js" as="script"><link rel="preload" href="/assets/js/291.6e1a6c9b.js" as="script"><link rel="prefetch" href="/assets/js/10.77e7d27b.js"><link rel="prefetch" href="/assets/js/100.ed95c785.js"><link rel="prefetch" href="/assets/js/101.824eb728.js"><link rel="prefetch" href="/assets/js/102.dfb385f3.js"><link rel="prefetch" href="/assets/js/103.b7b3c8f1.js"><link rel="prefetch" href="/assets/js/104.522d3ff0.js"><link rel="prefetch" href="/assets/js/105.b7388386.js"><link rel="prefetch" href="/assets/js/106.846b6bd8.js"><link rel="prefetch" href="/assets/js/107.2d9463c3.js"><link rel="prefetch" href="/assets/js/108.f245629a.js"><link rel="prefetch" href="/assets/js/109.69c25b06.js"><link rel="prefetch" href="/assets/js/11.a080efae.js"><link rel="prefetch" href="/assets/js/110.530a3a98.js"><link rel="prefetch" href="/assets/js/111.3b7a3ac1.js"><link rel="prefetch" href="/assets/js/112.f3812269.js"><link rel="prefetch" href="/assets/js/113.46505989.js"><link rel="prefetch" href="/assets/js/114.475c17a1.js"><link rel="prefetch" href="/assets/js/115.8b6c6d92.js"><link rel="prefetch" href="/assets/js/116.b394d6f1.js"><link rel="prefetch" href="/assets/js/117.31310d35.js"><link rel="prefetch" href="/assets/js/118.a42ab86c.js"><link rel="prefetch" href="/assets/js/119.07c43a65.js"><link rel="prefetch" href="/assets/js/12.30292c04.js"><link rel="prefetch" href="/assets/js/120.95c8a45a.js"><link rel="prefetch" href="/assets/js/121.163834bb.js"><link rel="prefetch" href="/assets/js/122.99015e01.js"><link rel="prefetch" href="/assets/js/123.b63b10d4.js"><link rel="prefetch" href="/assets/js/124.e5fcecb4.js"><link rel="prefetch" href="/assets/js/125.5d156960.js"><link rel="prefetch" href="/assets/js/126.21af8edc.js"><link rel="prefetch" href="/assets/js/127.94f1a74a.js"><link rel="prefetch" href="/assets/js/128.a5e03b1e.js"><link rel="prefetch" href="/assets/js/129.70d26ee1.js"><link rel="prefetch" href="/assets/js/13.ca90848f.js"><link rel="prefetch" href="/assets/js/130.866c33c2.js"><link rel="prefetch" href="/assets/js/131.e5ec8d01.js"><link rel="prefetch" href="/assets/js/132.1b2366a0.js"><link rel="prefetch" href="/assets/js/133.ad89487a.js"><link rel="prefetch" href="/assets/js/134.747a93d6.js"><link rel="prefetch" href="/assets/js/135.1e490c8b.js"><link rel="prefetch" href="/assets/js/136.8dacb951.js"><link rel="prefetch" href="/assets/js/137.4b220326.js"><link rel="prefetch" href="/assets/js/138.29265d0b.js"><link rel="prefetch" href="/assets/js/139.5ffbc26e.js"><link rel="prefetch" href="/assets/js/14.0518f057.js"><link rel="prefetch" href="/assets/js/140.bb3cd28c.js"><link rel="prefetch" href="/assets/js/141.f4cd2178.js"><link rel="prefetch" href="/assets/js/142.a070f8e2.js"><link rel="prefetch" href="/assets/js/143.9299561a.js"><link rel="prefetch" href="/assets/js/144.1f503a67.js"><link rel="prefetch" href="/assets/js/145.1c62a4d0.js"><link rel="prefetch" href="/assets/js/146.97d3e6eb.js"><link rel="prefetch" href="/assets/js/147.fdd69e02.js"><link rel="prefetch" href="/assets/js/148.542d0570.js"><link rel="prefetch" href="/assets/js/149.b6a0c0c4.js"><link rel="prefetch" href="/assets/js/15.0953eb10.js"><link rel="prefetch" href="/assets/js/150.47f1d515.js"><link rel="prefetch" href="/assets/js/151.52b9bd4e.js"><link rel="prefetch" href="/assets/js/152.d54e94e7.js"><link rel="prefetch" href="/assets/js/153.a3cb7b45.js"><link rel="prefetch" href="/assets/js/154.21b3e81c.js"><link rel="prefetch" href="/assets/js/155.8e74c6d3.js"><link rel="prefetch" href="/assets/js/156.f8866900.js"><link rel="prefetch" href="/assets/js/157.cceecfd1.js"><link rel="prefetch" href="/assets/js/158.f5424810.js"><link rel="prefetch" href="/assets/js/159.969149d7.js"><link rel="prefetch" href="/assets/js/16.be3a02b8.js"><link rel="prefetch" href="/assets/js/160.78670d5a.js"><link rel="prefetch" href="/assets/js/161.6ac36ecc.js"><link rel="prefetch" href="/assets/js/162.8e8f0b7a.js"><link rel="prefetch" href="/assets/js/163.be160611.js"><link rel="prefetch" href="/assets/js/164.f3391f5c.js"><link rel="prefetch" href="/assets/js/165.a50ca901.js"><link rel="prefetch" href="/assets/js/166.7e46ca06.js"><link rel="prefetch" href="/assets/js/167.e906027a.js"><link rel="prefetch" href="/assets/js/168.5dbef9ef.js"><link rel="prefetch" href="/assets/js/169.10dd3806.js"><link rel="prefetch" href="/assets/js/17.0dc295c9.js"><link rel="prefetch" href="/assets/js/170.6c329603.js"><link rel="prefetch" href="/assets/js/171.2feecdf1.js"><link rel="prefetch" href="/assets/js/172.95f87419.js"><link rel="prefetch" href="/assets/js/173.6f1d25bb.js"><link rel="prefetch" href="/assets/js/174.d86897c8.js"><link rel="prefetch" href="/assets/js/175.d5d0df6a.js"><link rel="prefetch" href="/assets/js/176.7eb83ad0.js"><link rel="prefetch" href="/assets/js/177.4e40876a.js"><link rel="prefetch" href="/assets/js/178.cae0d890.js"><link rel="prefetch" href="/assets/js/179.9b132ea4.js"><link rel="prefetch" href="/assets/js/18.6ec85d2f.js"><link rel="prefetch" href="/assets/js/180.88ff7121.js"><link rel="prefetch" href="/assets/js/181.f0d43fcc.js"><link rel="prefetch" href="/assets/js/182.7099cb48.js"><link rel="prefetch" href="/assets/js/183.edafdd83.js"><link rel="prefetch" href="/assets/js/184.4fc59e2c.js"><link rel="prefetch" href="/assets/js/185.36a5be8f.js"><link rel="prefetch" href="/assets/js/186.5dd1869c.js"><link rel="prefetch" href="/assets/js/187.3d35d396.js"><link rel="prefetch" href="/assets/js/188.c0bcf5ba.js"><link rel="prefetch" href="/assets/js/189.7a1a3e2e.js"><link rel="prefetch" href="/assets/js/19.515d3237.js"><link rel="prefetch" href="/assets/js/190.c3ae726f.js"><link rel="prefetch" href="/assets/js/191.d7e03656.js"><link rel="prefetch" href="/assets/js/192.a281a87e.js"><link rel="prefetch" href="/assets/js/193.df6d4718.js"><link rel="prefetch" href="/assets/js/194.b45804b4.js"><link rel="prefetch" href="/assets/js/195.8a4d26c7.js"><link rel="prefetch" href="/assets/js/196.e981220e.js"><link rel="prefetch" href="/assets/js/197.3444f6c7.js"><link rel="prefetch" href="/assets/js/198.0917f0fe.js"><link rel="prefetch" href="/assets/js/199.1c5dbeaf.js"><link rel="prefetch" href="/assets/js/20.43f89197.js"><link rel="prefetch" href="/assets/js/200.ae99c7c2.js"><link rel="prefetch" href="/assets/js/201.920840ef.js"><link rel="prefetch" href="/assets/js/202.9e1d7395.js"><link rel="prefetch" href="/assets/js/203.0480dc05.js"><link rel="prefetch" href="/assets/js/204.9e3b129d.js"><link rel="prefetch" href="/assets/js/205.8b96775b.js"><link rel="prefetch" href="/assets/js/206.16248e1d.js"><link rel="prefetch" href="/assets/js/207.08209c15.js"><link rel="prefetch" href="/assets/js/208.4e1a1fe8.js"><link rel="prefetch" href="/assets/js/209.684351e3.js"><link rel="prefetch" href="/assets/js/21.acbfa763.js"><link rel="prefetch" href="/assets/js/210.c7ec6d21.js"><link rel="prefetch" href="/assets/js/211.15611bfc.js"><link rel="prefetch" href="/assets/js/212.104e35e7.js"><link rel="prefetch" href="/assets/js/213.09979614.js"><link rel="prefetch" href="/assets/js/214.f1e6babb.js"><link rel="prefetch" href="/assets/js/215.047dc924.js"><link rel="prefetch" href="/assets/js/216.c7995b5f.js"><link rel="prefetch" href="/assets/js/217.2e6da777.js"><link rel="prefetch" href="/assets/js/218.79eaf6c1.js"><link rel="prefetch" href="/assets/js/219.83df5b4a.js"><link rel="prefetch" href="/assets/js/22.417af792.js"><link rel="prefetch" href="/assets/js/220.6dc448f7.js"><link rel="prefetch" href="/assets/js/221.9a9eebcd.js"><link rel="prefetch" href="/assets/js/222.dca39118.js"><link rel="prefetch" href="/assets/js/223.fb011059.js"><link rel="prefetch" href="/assets/js/224.cf6ca794.js"><link rel="prefetch" href="/assets/js/225.990885c8.js"><link rel="prefetch" href="/assets/js/226.e08365e2.js"><link rel="prefetch" href="/assets/js/227.31f28bb7.js"><link rel="prefetch" href="/assets/js/228.6de2676f.js"><link rel="prefetch" href="/assets/js/229.d5c30f16.js"><link rel="prefetch" href="/assets/js/23.6c7d7eea.js"><link rel="prefetch" href="/assets/js/230.88081b9a.js"><link rel="prefetch" href="/assets/js/231.a9d48e4f.js"><link rel="prefetch" href="/assets/js/232.3428e67a.js"><link rel="prefetch" href="/assets/js/233.6f3763a5.js"><link rel="prefetch" href="/assets/js/234.abbd03b2.js"><link rel="prefetch" href="/assets/js/235.ec25ed54.js"><link rel="prefetch" href="/assets/js/236.b977dbf2.js"><link rel="prefetch" href="/assets/js/237.66598776.js"><link rel="prefetch" href="/assets/js/238.694d8754.js"><link rel="prefetch" href="/assets/js/239.406e0531.js"><link rel="prefetch" href="/assets/js/24.a553bb19.js"><link rel="prefetch" href="/assets/js/240.854bedbf.js"><link rel="prefetch" href="/assets/js/241.5f8a330f.js"><link rel="prefetch" href="/assets/js/242.86e3c344.js"><link rel="prefetch" href="/assets/js/243.b561d8d3.js"><link rel="prefetch" href="/assets/js/244.f8b89521.js"><link rel="prefetch" href="/assets/js/245.d6222ec7.js"><link rel="prefetch" href="/assets/js/246.2b3fcc3e.js"><link rel="prefetch" href="/assets/js/247.43dfa612.js"><link rel="prefetch" href="/assets/js/248.4741dcd9.js"><link rel="prefetch" href="/assets/js/249.419ce16b.js"><link rel="prefetch" href="/assets/js/25.a807a864.js"><link rel="prefetch" href="/assets/js/250.f07ef0ee.js"><link rel="prefetch" href="/assets/js/251.c63f521d.js"><link rel="prefetch" href="/assets/js/252.811a7e8c.js"><link rel="prefetch" href="/assets/js/253.6d93c314.js"><link rel="prefetch" href="/assets/js/254.f315a0f9.js"><link rel="prefetch" href="/assets/js/255.18e2d69b.js"><link rel="prefetch" href="/assets/js/256.633166a4.js"><link rel="prefetch" href="/assets/js/257.ea907563.js"><link rel="prefetch" href="/assets/js/258.9431d26e.js"><link rel="prefetch" href="/assets/js/259.a02febe0.js"><link rel="prefetch" href="/assets/js/26.2121ac8d.js"><link rel="prefetch" href="/assets/js/260.a2e7e58f.js"><link rel="prefetch" href="/assets/js/261.cdbb6f97.js"><link rel="prefetch" href="/assets/js/262.8004896a.js"><link rel="prefetch" href="/assets/js/263.70e3fd11.js"><link rel="prefetch" href="/assets/js/264.a48b4ec3.js"><link rel="prefetch" href="/assets/js/265.34e42dc0.js"><link rel="prefetch" href="/assets/js/266.ca225af9.js"><link rel="prefetch" href="/assets/js/267.c1696137.js"><link rel="prefetch" href="/assets/js/268.4baa57e6.js"><link rel="prefetch" href="/assets/js/269.6e097d45.js"><link rel="prefetch" href="/assets/js/27.353617df.js"><link rel="prefetch" href="/assets/js/270.e5fa0340.js"><link rel="prefetch" href="/assets/js/271.7418d8b3.js"><link rel="prefetch" href="/assets/js/272.c03fdadb.js"><link rel="prefetch" href="/assets/js/273.c90f2a89.js"><link rel="prefetch" href="/assets/js/274.025000d2.js"><link rel="prefetch" href="/assets/js/275.785fd825.js"><link rel="prefetch" href="/assets/js/276.4658b553.js"><link rel="prefetch" href="/assets/js/277.be1d9950.js"><link rel="prefetch" href="/assets/js/278.969f62e9.js"><link rel="prefetch" href="/assets/js/279.b4687dca.js"><link rel="prefetch" href="/assets/js/28.de5fbffd.js"><link rel="prefetch" href="/assets/js/280.066a8f96.js"><link rel="prefetch" href="/assets/js/281.97979cbe.js"><link rel="prefetch" href="/assets/js/282.d209138a.js"><link rel="prefetch" href="/assets/js/283.c3249204.js"><link rel="prefetch" href="/assets/js/284.ac2bf191.js"><link rel="prefetch" href="/assets/js/285.bca6aa40.js"><link rel="prefetch" href="/assets/js/286.6cbe9274.js"><link rel="prefetch" href="/assets/js/287.088fa473.js"><link rel="prefetch" href="/assets/js/288.a1f73477.js"><link rel="prefetch" href="/assets/js/289.659caaed.js"><link rel="prefetch" href="/assets/js/29.91dc2824.js"><link rel="prefetch" href="/assets/js/290.f024ff5f.js"><link rel="prefetch" href="/assets/js/292.598d841f.js"><link rel="prefetch" href="/assets/js/293.cd2df0cc.js"><link rel="prefetch" href="/assets/js/294.49874dd4.js"><link rel="prefetch" href="/assets/js/295.0dac4d0b.js"><link rel="prefetch" href="/assets/js/296.8f353ed4.js"><link rel="prefetch" href="/assets/js/297.3bb42d7a.js"><link rel="prefetch" href="/assets/js/298.91b1b31c.js"><link rel="prefetch" href="/assets/js/299.348f494c.js"><link rel="prefetch" href="/assets/js/30.03cf4852.js"><link rel="prefetch" href="/assets/js/300.9a839ae2.js"><link rel="prefetch" href="/assets/js/301.5972ea62.js"><link rel="prefetch" href="/assets/js/302.03d8c96e.js"><link rel="prefetch" href="/assets/js/303.10880519.js"><link rel="prefetch" href="/assets/js/304.0d8f585e.js"><link rel="prefetch" href="/assets/js/305.fc662c9f.js"><link rel="prefetch" href="/assets/js/306.fe8e18f6.js"><link rel="prefetch" href="/assets/js/307.32cbfa3d.js"><link rel="prefetch" href="/assets/js/308.85fb07ff.js"><link rel="prefetch" href="/assets/js/309.2ea57d84.js"><link rel="prefetch" href="/assets/js/31.4b8359e5.js"><link rel="prefetch" href="/assets/js/310.e410f107.js"><link rel="prefetch" href="/assets/js/311.6eaf26c4.js"><link rel="prefetch" href="/assets/js/312.c9ecb92c.js"><link rel="prefetch" href="/assets/js/313.826db8cd.js"><link rel="prefetch" href="/assets/js/314.7f57565d.js"><link rel="prefetch" href="/assets/js/315.8130feb6.js"><link rel="prefetch" href="/assets/js/316.41b61be0.js"><link rel="prefetch" href="/assets/js/317.a2ea3d95.js"><link rel="prefetch" href="/assets/js/318.5f3975f5.js"><link rel="prefetch" href="/assets/js/319.743e01f9.js"><link rel="prefetch" href="/assets/js/32.6fe577bc.js"><link rel="prefetch" href="/assets/js/320.f461a416.js"><link rel="prefetch" href="/assets/js/321.c7a56cb3.js"><link rel="prefetch" href="/assets/js/322.678b2aa6.js"><link rel="prefetch" href="/assets/js/323.c1402dc9.js"><link rel="prefetch" href="/assets/js/324.5e31b5b7.js"><link rel="prefetch" href="/assets/js/325.85d7b6f2.js"><link rel="prefetch" href="/assets/js/326.2aad02c9.js"><link rel="prefetch" href="/assets/js/327.a2797c70.js"><link rel="prefetch" href="/assets/js/328.eab6f5e8.js"><link rel="prefetch" href="/assets/js/329.1fcd30fb.js"><link rel="prefetch" href="/assets/js/33.d0eafbb9.js"><link rel="prefetch" href="/assets/js/330.d6814502.js"><link rel="prefetch" href="/assets/js/331.aaef2a2d.js"><link rel="prefetch" href="/assets/js/332.25c3698e.js"><link rel="prefetch" href="/assets/js/333.ff760597.js"><link rel="prefetch" href="/assets/js/334.4352a701.js"><link rel="prefetch" href="/assets/js/335.a08d4648.js"><link rel="prefetch" href="/assets/js/336.adbfcd2a.js"><link rel="prefetch" href="/assets/js/337.91b7a655.js"><link rel="prefetch" href="/assets/js/338.527a995c.js"><link rel="prefetch" href="/assets/js/339.17770dae.js"><link rel="prefetch" href="/assets/js/34.85849ed4.js"><link rel="prefetch" href="/assets/js/340.5e3f5af3.js"><link rel="prefetch" href="/assets/js/341.6f3254cc.js"><link rel="prefetch" href="/assets/js/342.eb19c5b2.js"><link rel="prefetch" href="/assets/js/343.86880c2b.js"><link rel="prefetch" href="/assets/js/344.b246b989.js"><link rel="prefetch" href="/assets/js/345.fc088fdc.js"><link rel="prefetch" href="/assets/js/346.b959a237.js"><link rel="prefetch" href="/assets/js/347.6936a722.js"><link rel="prefetch" href="/assets/js/348.d0bee38d.js"><link rel="prefetch" href="/assets/js/349.4d751508.js"><link rel="prefetch" href="/assets/js/35.5612ab6a.js"><link rel="prefetch" href="/assets/js/350.0e29054a.js"><link rel="prefetch" href="/assets/js/351.085e1aa5.js"><link rel="prefetch" href="/assets/js/352.6cc96e5d.js"><link rel="prefetch" href="/assets/js/353.cfe4cf8b.js"><link rel="prefetch" href="/assets/js/354.88283483.js"><link rel="prefetch" href="/assets/js/355.c6db4669.js"><link rel="prefetch" href="/assets/js/356.c5a04c75.js"><link rel="prefetch" href="/assets/js/357.698b5c48.js"><link rel="prefetch" href="/assets/js/358.a1284b35.js"><link rel="prefetch" href="/assets/js/359.04925c9a.js"><link rel="prefetch" href="/assets/js/36.4e36f97e.js"><link rel="prefetch" href="/assets/js/360.9daae8bf.js"><link rel="prefetch" href="/assets/js/361.f9736519.js"><link rel="prefetch" href="/assets/js/362.746e9925.js"><link rel="prefetch" href="/assets/js/363.c296153b.js"><link rel="prefetch" href="/assets/js/364.79bb95e0.js"><link rel="prefetch" href="/assets/js/365.19b72317.js"><link rel="prefetch" href="/assets/js/366.46fbd6f7.js"><link rel="prefetch" href="/assets/js/367.78a65da6.js"><link rel="prefetch" href="/assets/js/368.b734ee75.js"><link rel="prefetch" href="/assets/js/369.6a0f730e.js"><link rel="prefetch" href="/assets/js/37.33185238.js"><link rel="prefetch" href="/assets/js/370.ca1215ed.js"><link rel="prefetch" href="/assets/js/371.c1d1c747.js"><link rel="prefetch" href="/assets/js/372.b9e57899.js"><link rel="prefetch" href="/assets/js/373.aa42888a.js"><link rel="prefetch" href="/assets/js/374.6e77b7d2.js"><link rel="prefetch" href="/assets/js/375.f88c3c53.js"><link rel="prefetch" href="/assets/js/376.480dacf6.js"><link rel="prefetch" href="/assets/js/377.6f48920f.js"><link rel="prefetch" href="/assets/js/378.e839a0d7.js"><link rel="prefetch" href="/assets/js/379.fab165fa.js"><link rel="prefetch" href="/assets/js/38.b02b6af6.js"><link rel="prefetch" href="/assets/js/380.3b479eee.js"><link rel="prefetch" href="/assets/js/381.13c45e12.js"><link rel="prefetch" href="/assets/js/382.b9d10d79.js"><link rel="prefetch" href="/assets/js/383.22938fc1.js"><link rel="prefetch" href="/assets/js/384.aa932ca6.js"><link rel="prefetch" href="/assets/js/385.3bf09de9.js"><link rel="prefetch" href="/assets/js/386.8894c43f.js"><link rel="prefetch" href="/assets/js/387.3b662ff8.js"><link rel="prefetch" href="/assets/js/388.a1ae1ede.js"><link rel="prefetch" href="/assets/js/389.3dab322c.js"><link rel="prefetch" href="/assets/js/39.bdef8540.js"><link rel="prefetch" href="/assets/js/390.336a9553.js"><link rel="prefetch" href="/assets/js/391.da4afab5.js"><link rel="prefetch" href="/assets/js/392.c7097ee6.js"><link rel="prefetch" href="/assets/js/393.2add8d8b.js"><link rel="prefetch" href="/assets/js/394.01a05f68.js"><link rel="prefetch" href="/assets/js/395.f87beb80.js"><link rel="prefetch" href="/assets/js/396.1ea42313.js"><link rel="prefetch" href="/assets/js/397.3b2c4329.js"><link rel="prefetch" href="/assets/js/398.e19b2769.js"><link rel="prefetch" href="/assets/js/399.959cde76.js"><link rel="prefetch" href="/assets/js/4.a195f7b6.js"><link rel="prefetch" href="/assets/js/40.83fa7936.js"><link rel="prefetch" href="/assets/js/400.81bf6971.js"><link rel="prefetch" href="/assets/js/401.917f34b9.js"><link rel="prefetch" href="/assets/js/402.b9b6b243.js"><link rel="prefetch" href="/assets/js/403.d18ffde3.js"><link rel="prefetch" href="/assets/js/404.f05efd75.js"><link rel="prefetch" href="/assets/js/405.f0a294d4.js"><link rel="prefetch" href="/assets/js/406.3d6728bf.js"><link rel="prefetch" href="/assets/js/407.9db8bc05.js"><link rel="prefetch" href="/assets/js/408.ee74e96c.js"><link rel="prefetch" href="/assets/js/409.908ee17a.js"><link rel="prefetch" href="/assets/js/41.3693bb5f.js"><link rel="prefetch" href="/assets/js/410.19de2693.js"><link rel="prefetch" href="/assets/js/411.126a0e61.js"><link rel="prefetch" href="/assets/js/412.0714380f.js"><link rel="prefetch" href="/assets/js/413.548508ac.js"><link rel="prefetch" href="/assets/js/414.7e20a18c.js"><link rel="prefetch" href="/assets/js/415.8973dc73.js"><link rel="prefetch" href="/assets/js/416.ed747810.js"><link rel="prefetch" href="/assets/js/417.69aff868.js"><link rel="prefetch" href="/assets/js/418.d08b9633.js"><link rel="prefetch" href="/assets/js/419.7a29a575.js"><link rel="prefetch" href="/assets/js/42.d7b203f7.js"><link rel="prefetch" href="/assets/js/420.e1b32755.js"><link rel="prefetch" href="/assets/js/421.9f59b9c4.js"><link rel="prefetch" href="/assets/js/422.82338d23.js"><link rel="prefetch" href="/assets/js/423.78ae5544.js"><link rel="prefetch" href="/assets/js/424.58ec76aa.js"><link rel="prefetch" href="/assets/js/425.44ee0a9c.js"><link rel="prefetch" href="/assets/js/426.35170657.js"><link rel="prefetch" href="/assets/js/427.b96b2653.js"><link rel="prefetch" href="/assets/js/428.789479d6.js"><link rel="prefetch" href="/assets/js/429.cfd12490.js"><link rel="prefetch" href="/assets/js/43.f4a347ba.js"><link rel="prefetch" href="/assets/js/430.22ab1959.js"><link rel="prefetch" href="/assets/js/431.58e8895f.js"><link rel="prefetch" href="/assets/js/432.8f6c6e43.js"><link rel="prefetch" href="/assets/js/433.128fd68b.js"><link rel="prefetch" href="/assets/js/434.cb6df7fd.js"><link rel="prefetch" href="/assets/js/435.596e9910.js"><link rel="prefetch" href="/assets/js/436.2a426362.js"><link rel="prefetch" href="/assets/js/437.c4e29f95.js"><link rel="prefetch" href="/assets/js/438.60eead82.js"><link rel="prefetch" href="/assets/js/439.755047ee.js"><link rel="prefetch" href="/assets/js/44.b334ed25.js"><link rel="prefetch" href="/assets/js/440.eadeab90.js"><link rel="prefetch" href="/assets/js/441.2fd0022c.js"><link rel="prefetch" href="/assets/js/442.5febb7ff.js"><link rel="prefetch" href="/assets/js/443.40d31ee9.js"><link rel="prefetch" href="/assets/js/444.2ae6c97b.js"><link rel="prefetch" href="/assets/js/445.358eb5a0.js"><link rel="prefetch" href="/assets/js/446.f70aa844.js"><link rel="prefetch" href="/assets/js/447.e57098da.js"><link rel="prefetch" href="/assets/js/448.42fa449f.js"><link rel="prefetch" href="/assets/js/449.87a7d812.js"><link rel="prefetch" href="/assets/js/45.20484792.js"><link rel="prefetch" href="/assets/js/450.2d5c62cb.js"><link rel="prefetch" href="/assets/js/451.cfb7d1c7.js"><link rel="prefetch" href="/assets/js/452.d4ca93d8.js"><link rel="prefetch" href="/assets/js/453.f3859daa.js"><link rel="prefetch" href="/assets/js/454.bb599f94.js"><link rel="prefetch" href="/assets/js/455.164435bc.js"><link rel="prefetch" href="/assets/js/456.3a24aaab.js"><link rel="prefetch" href="/assets/js/457.be959948.js"><link rel="prefetch" href="/assets/js/458.94bcefe5.js"><link rel="prefetch" href="/assets/js/459.d4dbc24e.js"><link rel="prefetch" href="/assets/js/46.508f7d41.js"><link rel="prefetch" href="/assets/js/460.1abdd421.js"><link rel="prefetch" href="/assets/js/461.3b85e094.js"><link rel="prefetch" href="/assets/js/462.328088b4.js"><link rel="prefetch" href="/assets/js/463.8f458fe3.js"><link rel="prefetch" href="/assets/js/464.4799603d.js"><link rel="prefetch" href="/assets/js/465.4510e882.js"><link rel="prefetch" href="/assets/js/466.01245050.js"><link rel="prefetch" href="/assets/js/467.2ca7baa4.js"><link rel="prefetch" href="/assets/js/468.471e2d1f.js"><link rel="prefetch" href="/assets/js/469.bfffaee9.js"><link rel="prefetch" href="/assets/js/47.a8742825.js"><link rel="prefetch" href="/assets/js/470.97799d73.js"><link rel="prefetch" href="/assets/js/471.05120819.js"><link rel="prefetch" href="/assets/js/472.3892f52c.js"><link rel="prefetch" href="/assets/js/473.be27ddaa.js"><link rel="prefetch" href="/assets/js/474.9e1d826e.js"><link rel="prefetch" href="/assets/js/475.4bbf0340.js"><link rel="prefetch" href="/assets/js/476.43ad6812.js"><link rel="prefetch" href="/assets/js/477.79abdb61.js"><link rel="prefetch" href="/assets/js/478.99ac7b26.js"><link rel="prefetch" href="/assets/js/479.978b51aa.js"><link rel="prefetch" href="/assets/js/48.ad2c2a29.js"><link rel="prefetch" href="/assets/js/480.682076e4.js"><link rel="prefetch" href="/assets/js/481.592b3459.js"><link rel="prefetch" href="/assets/js/482.51200cc2.js"><link rel="prefetch" href="/assets/js/483.5a48543e.js"><link rel="prefetch" href="/assets/js/484.a7cb9e3e.js"><link rel="prefetch" href="/assets/js/485.a920105c.js"><link rel="prefetch" href="/assets/js/486.7a12b540.js"><link rel="prefetch" href="/assets/js/487.78f9b7c4.js"><link rel="prefetch" href="/assets/js/488.182ede16.js"><link rel="prefetch" href="/assets/js/489.7cdb000a.js"><link rel="prefetch" href="/assets/js/49.a22d6593.js"><link rel="prefetch" href="/assets/js/490.f80db158.js"><link rel="prefetch" href="/assets/js/491.a60a3324.js"><link rel="prefetch" href="/assets/js/492.db35e960.js"><link rel="prefetch" href="/assets/js/493.5bc91ef5.js"><link rel="prefetch" href="/assets/js/494.59430cc4.js"><link rel="prefetch" href="/assets/js/495.8f890f74.js"><link rel="prefetch" href="/assets/js/496.0d962a47.js"><link rel="prefetch" href="/assets/js/497.d01e6f25.js"><link rel="prefetch" href="/assets/js/498.91583855.js"><link rel="prefetch" href="/assets/js/499.dad0cd86.js"><link rel="prefetch" href="/assets/js/5.2a4451ec.js"><link rel="prefetch" href="/assets/js/50.7d8944cd.js"><link rel="prefetch" href="/assets/js/500.4fef98e6.js"><link rel="prefetch" href="/assets/js/501.70c8ab6c.js"><link rel="prefetch" href="/assets/js/502.647791b2.js"><link rel="prefetch" href="/assets/js/503.e27cca34.js"><link rel="prefetch" href="/assets/js/504.d255dfd4.js"><link rel="prefetch" href="/assets/js/505.8ebc01bb.js"><link rel="prefetch" href="/assets/js/506.96eff784.js"><link rel="prefetch" href="/assets/js/507.ee0941f8.js"><link rel="prefetch" href="/assets/js/508.eca87bfc.js"><link rel="prefetch" href="/assets/js/509.ac852d9e.js"><link rel="prefetch" href="/assets/js/51.fd01b1a1.js"><link rel="prefetch" href="/assets/js/510.f2c30f30.js"><link rel="prefetch" href="/assets/js/511.93c39252.js"><link rel="prefetch" href="/assets/js/512.6693c6d2.js"><link rel="prefetch" href="/assets/js/513.a093308f.js"><link rel="prefetch" href="/assets/js/514.586fc8e9.js"><link rel="prefetch" href="/assets/js/515.4b42a743.js"><link rel="prefetch" href="/assets/js/516.1776d737.js"><link rel="prefetch" href="/assets/js/517.34d50a8b.js"><link rel="prefetch" href="/assets/js/518.1ddd9cd6.js"><link rel="prefetch" href="/assets/js/519.4b8d67f9.js"><link rel="prefetch" href="/assets/js/52.10d8a15b.js"><link rel="prefetch" href="/assets/js/520.72b60177.js"><link rel="prefetch" href="/assets/js/521.208e1056.js"><link rel="prefetch" href="/assets/js/522.0b70667a.js"><link rel="prefetch" href="/assets/js/523.c5baafd0.js"><link rel="prefetch" href="/assets/js/524.a0faf49c.js"><link rel="prefetch" href="/assets/js/525.5e8c24b2.js"><link rel="prefetch" href="/assets/js/526.2a0914f9.js"><link rel="prefetch" href="/assets/js/527.ded91633.js"><link rel="prefetch" href="/assets/js/528.afaf3a7c.js"><link rel="prefetch" href="/assets/js/53.29fda513.js"><link rel="prefetch" href="/assets/js/54.1ec48dc5.js"><link rel="prefetch" href="/assets/js/55.38876710.js"><link rel="prefetch" href="/assets/js/56.aa94202c.js"><link rel="prefetch" href="/assets/js/57.4487fe4e.js"><link rel="prefetch" href="/assets/js/58.fce3a269.js"><link rel="prefetch" href="/assets/js/59.f956ceb1.js"><link rel="prefetch" href="/assets/js/6.3450075a.js"><link rel="prefetch" href="/assets/js/60.04e971a8.js"><link rel="prefetch" href="/assets/js/61.39ed191f.js"><link rel="prefetch" href="/assets/js/62.eef65e9b.js"><link rel="prefetch" href="/assets/js/63.49f75809.js"><link rel="prefetch" href="/assets/js/64.ca5c6060.js"><link rel="prefetch" href="/assets/js/65.caf7d783.js"><link rel="prefetch" href="/assets/js/66.5ec349a5.js"><link rel="prefetch" href="/assets/js/67.29edf638.js"><link rel="prefetch" href="/assets/js/68.de6ad154.js"><link rel="prefetch" href="/assets/js/69.71328eaf.js"><link rel="prefetch" href="/assets/js/7.c5c54fb4.js"><link rel="prefetch" href="/assets/js/70.5e78a4e5.js"><link rel="prefetch" href="/assets/js/71.64856643.js"><link rel="prefetch" href="/assets/js/72.8010c02a.js"><link rel="prefetch" href="/assets/js/73.498829e1.js"><link rel="prefetch" href="/assets/js/74.df0d04bd.js"><link rel="prefetch" href="/assets/js/75.a230e9c2.js"><link rel="prefetch" href="/assets/js/76.79d37682.js"><link rel="prefetch" href="/assets/js/77.d93d9983.js"><link rel="prefetch" href="/assets/js/78.1f320f90.js"><link rel="prefetch" href="/assets/js/79.036924ec.js"><link rel="prefetch" href="/assets/js/8.de5c69e7.js"><link rel="prefetch" href="/assets/js/80.293948a6.js"><link rel="prefetch" href="/assets/js/81.fcfc5c23.js"><link rel="prefetch" href="/assets/js/82.418c0deb.js"><link rel="prefetch" href="/assets/js/83.3720138d.js"><link rel="prefetch" href="/assets/js/84.e4ab62ab.js"><link rel="prefetch" href="/assets/js/85.a51ccec4.js"><link rel="prefetch" href="/assets/js/86.af367a23.js"><link rel="prefetch" href="/assets/js/87.208096b5.js"><link rel="prefetch" href="/assets/js/88.6d82fdfa.js"><link rel="prefetch" href="/assets/js/89.855e8d78.js"><link rel="prefetch" href="/assets/js/9.18fb6454.js"><link rel="prefetch" href="/assets/js/90.35f0b664.js"><link rel="prefetch" href="/assets/js/91.f05d3514.js"><link rel="prefetch" href="/assets/js/92.c427e959.js"><link rel="prefetch" href="/assets/js/93.301dbd74.js"><link rel="prefetch" href="/assets/js/94.df22e216.js"><link rel="prefetch" href="/assets/js/95.96ae29e6.js"><link rel="prefetch" href="/assets/js/96.2a84236c.js"><link rel="prefetch" href="/assets/js/97.9921cd09.js"><link rel="prefetch" href="/assets/js/98.ac175dbc.js"><link rel="prefetch" href="/assets/js/99.ed51aa2e.js"><link rel="prefetch" href="/assets/js/vendors~docsearch.eff714eb.js"> |
| <link rel="stylesheet" href="/assets/css/0.styles.ccadf850.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="/zh/" 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">文档</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/zh/UserGuide/Master/Get Started/QuickStart.html" class="nav-link">In progress</a></li><li class="dropdown-item"><!----> <a href="/zh/UserGuide/V0.11.x/Get Started/QuickStart.html" class="nav-link">V0.11.x</a></li><li class="dropdown-item"><!----> <a href="/zh/UserGuide/V0.10.x/Get Started/QuickStart.html" class="nav-link">V0.10.x</a></li><li class="dropdown-item"><!----> <a href="/zh/UserGuide/V0.9.x/0-Get Started/1-QuickStart.html" class="nav-link">V0.9.x</a></li><li class="dropdown-item"><!----> <a href="/zh/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="/zh/SystemDesign/Architecture/Architecture.html" class="nav-link">系统设计</a></div><div class="nav-item"><a href="/zh/Download/" class="nav-link">下载</a></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">社区</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="/zh/Community/Community-Project Committers.html" class="nav-link">开发人员</a></li><li class="dropdown-item"><!----> <a href="/zh/Community/Community-Powered By.html" class="nav-link">技术支持</a></li><li class="dropdown-item"><!----> <a href="/Community/Materials.html" class="nav-link">活动与报告</a></li><li class="dropdown-item"><!----> <a href="/zh/Community/Feedback.html" class="nav-link">交流与反馈</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">开发</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/zh/Development/VoteRelease.html" class="nav-link">如何投票</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/HowToCommit.html" class="nav-link">如何提交代码</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/Committer.html" class="nav-link">成为Committer</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/ContributeGuide.html" class="nav-link">项目开发指南</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/format-changelist.html" class="nav-link">TsFile的更改列表</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/rpc-changelist.html" class="nav-link">RPC变更清单</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"> |
| 基金会 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/licenses/" class="nav-link external"> |
| 许可证 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/security/" class="nav-link external"> |
| 安全 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/foundation/sponsorship.html" class="nav-link external"> |
| 赞助 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/foundation/thanks.html" class="nav-link external"> |
| 致谢 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/events/current-event" class="nav-link external"> |
| 活动 |
| <!----></a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">语言</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/SystemDesign/DataQuery/GroupByFillQuery.html" class="nav-link">English</a></li><li class="dropdown-item"><!----> <a href="/zh/SystemDesign/DataQuery/GroupByFillQuery.html" aria-current="page" class="nav-link router-link-exact-active router-link-active">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">文档</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/zh/UserGuide/Master/Get Started/QuickStart.html" class="nav-link">In progress</a></li><li class="dropdown-item"><!----> <a href="/zh/UserGuide/V0.11.x/Get Started/QuickStart.html" class="nav-link">V0.11.x</a></li><li class="dropdown-item"><!----> <a href="/zh/UserGuide/V0.10.x/Get Started/QuickStart.html" class="nav-link">V0.10.x</a></li><li class="dropdown-item"><!----> <a href="/zh/UserGuide/V0.9.x/0-Get Started/1-QuickStart.html" class="nav-link">V0.9.x</a></li><li class="dropdown-item"><!----> <a href="/zh/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="/zh/SystemDesign/Architecture/Architecture.html" class="nav-link">系统设计</a></div><div class="nav-item"><a href="/zh/Download/" class="nav-link">下载</a></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">社区</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="/zh/Community/Community-Project Committers.html" class="nav-link">开发人员</a></li><li class="dropdown-item"><!----> <a href="/zh/Community/Community-Powered By.html" class="nav-link">技术支持</a></li><li class="dropdown-item"><!----> <a href="/Community/Materials.html" class="nav-link">活动与报告</a></li><li class="dropdown-item"><!----> <a href="/zh/Community/Feedback.html" class="nav-link">交流与反馈</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">开发</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/zh/Development/VoteRelease.html" class="nav-link">如何投票</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/HowToCommit.html" class="nav-link">如何提交代码</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/Committer.html" class="nav-link">成为Committer</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/ContributeGuide.html" class="nav-link">项目开发指南</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/format-changelist.html" class="nav-link">TsFile的更改列表</a></li><li class="dropdown-item"><!----> <a href="/zh/Development/rpc-changelist.html" class="nav-link">RPC变更清单</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"> |
| 基金会 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/licenses/" class="nav-link external"> |
| 许可证 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/security/" class="nav-link external"> |
| 安全 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/foundation/sponsorship.html" class="nav-link external"> |
| 赞助 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/foundation/thanks.html" class="nav-link external"> |
| 致谢 |
| <!----></a></li><li class="dropdown-item"><!----> <a href="http://www.apache.org/events/current-event" class="nav-link external"> |
| 活动 |
| <!----></a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><a class="dropdown-title"><span class="title">语言</span> <span class="arrow right"></span></a> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/SystemDesign/DataQuery/GroupByFillQuery.html" class="nav-link">English</a></li><li class="dropdown-item"><!----> <a href="/zh/SystemDesign/DataQuery/GroupByFillQuery.html" aria-current="page" class="nav-link router-link-exact-active router-link-active">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>系统设计</span> <!----></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>应用概览</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>查询引擎</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>元数据管理</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>存储引擎</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading open"><span>数据查询</span> <span class="arrow down"></span></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/zh/SystemDesign/DataQuery/DataQuery.html" class="sidebar-link">数据查询</a></li><li><a href="/zh/SystemDesign/DataQuery/QueryFundamentals.html" class="sidebar-link">查询基础介绍</a></li><li><a href="/zh/SystemDesign/DataQuery/SeriesReader.html" class="sidebar-link">查询基础组件</a></li><li><a href="/zh/SystemDesign/DataQuery/RawDataQuery.html" class="sidebar-link">原始数据查询</a></li><li><a href="/zh/SystemDesign/DataQuery/AggregationQuery.html" class="sidebar-link">聚合查询</a></li><li><a href="/zh/SystemDesign/DataQuery/GroupByQuery.html" class="sidebar-link">降采样查询</a></li><li><a href="/zh/SystemDesign/DataQuery/LastQuery.html" class="sidebar-link">最近时间戳 Last 查询</a></li><li><a href="/zh/SystemDesign/DataQuery/AlignByDeviceQuery.html" class="sidebar-link">按设备对齐查询</a></li><li><a href="/zh/SystemDesign/DataQuery/FillFunction.html" class="sidebar-link">空值填充</a></li><li><a href="/zh/SystemDesign/DataQuery/GroupByFillQuery.html" aria-current="page" class="active sidebar-link">降采样补空值查询</a></li><li><a href="/zh/SystemDesign/DataQuery/OrderByTimeQuery.html" class="sidebar-link">按时间倒序查询</a></li></ul></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>工具</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>连接器</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>客户端</span> <span class="arrow right"></span></p> <!----></section></li></ul> </aside> <main class="page"> <div class="content content__default"><h1 id="降采样补空值查询"><a href="#降采样补空值查询" class="header-anchor">#</a> 降采样补空值查询</h1> <p>GroupByFill 查询的主要逻辑在 <code>GroupByFillDataSet</code></p> <ul><li><code>org.apache.iotdb.db.query.dataset.groupby.GroupByFillDataSet</code></li></ul> <p>GroupByFill是对原降采样结果进行填充，目前仅支持使用前值填充的方式。</p> <ul><li>在Group By Fill中，Group by子句不支持滑动步长，否则抛异常</li> <li>Fill子句中仅能使用Previous和PREVIOUSUNTILLAST这两种插值方式，Linear不支持</li> <li>Previous和PREVIOUSUNTILLAST对fill的时间不做限制</li> <li>填充只针对last_value这一聚合函数，其他的函数不支持，如果其他函数的聚合值查询结果为null，依旧为null，不进行填充</li></ul> <h2 id="previousuntillast与previous填充的区别"><a href="#previousuntillast与previous填充的区别" class="header-anchor">#</a> PREVIOUSUNTILLAST与PREVIOUS填充的区别</h2> <p>Previous填充方式的语意没有变，只要前面有值，就可以拿过来填充； |
| PREVIOUSUNTILLAST考虑到在某些业务场景下，所填充的值的时间不能大于该时间序列last的时间戳（从业务角度考虑，取历史数据不能取未来历史数据） |
| 看下面的例子，或许更容易理解</p> <p>A点时间戳为1，B为5，C为20，D为30，N为8，M为38</p> <p>原始数据为<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 >= 1 and time <= 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>当我们使用Previous插值方式时，即使D到M这一段是未来的数据，我们也会用D点的数据进行填充</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>当我们使用NONLASTPREVIOUS插值方式时，因为D到M这一段是未来的数据，我们不会进行插值，还是返回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="核心查询逻辑"><a href="#核心查询逻辑" class="header-anchor">#</a> 核心查询逻辑</h2> <p>在<code>GroupByFillDataSet</code>中维护了两个主要变量</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>这个变量维护了当前时间窗口的前一个降采样值，在<code>GroupByFillDataSet</code>构造函数中调用了<code>initPreviousParis</code>方法对其进行初始化。</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 < 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>方法主要为每个时间序列构造了一个单点补空值查询，<code>queryTime</code>设置为降采样时间窗口的起始值，<code>beforeRange</code>不作限制。</p> <h3 id="lasttimearray"><a href="#lasttimearray" class="header-anchor">#</a> <code>lastTimeArray</code></h3> <p><code>lastTimeArray</code>这个变量维护了每个时间序列的最近时间戳值，主要用于<code>PREVIOUSUNTILLAST</code>这一填充方式，在<code>GroupByFillDataSet</code>构造函数中调用了<code>initLastTimeArray</code>方法对其进行初始化。</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 < 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>方法主要为每个时间序列构造了一个最近时间戳 Last 查询</p> <h3 id="填充过程"><a href="#填充过程" class="header-anchor">#</a> 填充过程</h3> <p>填充过程在<code>nextWithoutConstraint</code>方法中完成，主要逻辑如下：</p> <div class="language- line-numbers-mode"><pre class="language-text"><code>protected RowRecord nextWithoutConstraint() throws IOException { |
| |
| // 首先通过groupByEngineDataSet，获得原始的降采样查询结果行 |
| RowRecord rowRecord = groupByEngineDataSet.nextWithoutConstraint(); |
| |
| // 接下来对每个时间序列判断需不需要填充 |
| for (int i = 0; i < paths.size(); i++) { |
| Field field = rowRecord.getFields().get(i); |
| // 当前值为null，需要进行填充 |
| if (field.getDataType() == null) { |
| // 当前一个值不为null 并且 (填充方式不是PREVIOUSUNTILLAST 或者 当前时间小于改时间序列的最近时间戳) |
| if (previousValue[i] != null |
| && (!((PreviousFill) fillTypes.get(dataTypes.get(i))).isUntilLast() |
| || rowRecord.getTimestamp() <= lastTimeArray[i])) { |
| rowRecord.getFields().set(i, Field.getField(previousValue[i], dataTypes.get(i))); |
| } |
| } else { |
| // 当前值不为null，不需要填充，用当前值更新previousValue数组 |
| 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></div></div></div> <div class="page-nav"><p class="inner"><span class="prev"> |
| ← |
| <a href="/zh/SystemDesign/DataQuery/FillFunction.html" class="prev"> |
| 空值填充 |
| </a></span> <span class="next"><a href="/zh/SystemDesign/DataQuery/OrderByTimeQuery.html"> |
| 按时间倒序查询 |
| </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.821c382f.js" defer></script><script src="/assets/js/3.5626571b.js" defer></script><script src="/assets/js/291.6e1a6c9b.js" defer></script> |
| </body> |
| </html> |
