ClickHouseMATERIALIZEDVIEW

1、0、原理物化視圖的原理是服務(wù)器覺得空閑的時(shí)候，幫你做一次select再insert的動(dòng)作，可以通過物化視圖來實(shí)現(xiàn)表間數(shù)據(jù)復(fù)制。*配置parallel_view_processing來實(shí)現(xiàn)物化視圖是同步還是異步與。物化視圖也是一個(gè)普通的表。payattention:物化視圖不能修改表名1、可以用來實(shí)現(xiàn)什么？當(dāng)有需要在同個(gè)實(shí)例進(jìn)行多表多寫的時(shí)候，就可以使用物化視圖來實(shí)現(xiàn)ClickHouse幫你做表的數(shù)據(jù)復(fù)制，減少了多寫的帶寬消耗，降低集群負(fù)載。適用場景：需要有多個(gè)時(shí)間維度的表同一個(gè)表需要建立不同的索引粒度2、怎么用？CREATEMATERIALIZEDVIEWdb.tableENGINE=Merg

2、eTree()PARTITIONBYdayORDERBYnameASSELECT*FROMdb.old-table;如果需要實(shí)現(xiàn)多個(gè)時(shí)間維度的表，則ASSELECT的時(shí)候?qū)r(shí)間字段多處理即可實(shí)現(xiàn)3、測試對(duì)6w/s寫入量級(jí)的原始表進(jìn)行測試(1)數(shù)據(jù)完整度原始表sumfalLcount)YtoD3t&Tirn÷(5tatistic_timerlOGOj7171992.8732019-12-2117:19:0071,945,0982019-12-2117:18200718237602019-12-2117:17i0&72,016,8172019-12-2117:16:007Z187323

3、2019-12-2117:15:0071,973,7632019*12-2117:14:0071074,2302019-12-2117:13:00原始表.png物化視圖125血訓(xùn)joint)Vcount(l)H0toDateTimefdividefstatisticjime.1000)肚7腳1252肝552019-12-2117:19:007叮4262328,6602019-12-2117:18:00712013滋7712019-12-2117:17:007201530625.7222019-12-2117:16:00物化視圖.png可以看到，數(shù)據(jù)完整度在99.99%以上。(2)復(fù)制時(shí)效性原始

4、表I23sumall_counfl7+QtoDateTimetdividettatisticjime.LOOT1.2712019-12-2117:37:001,1662019-12-2117:36:004,201762019-12-2117:35:002W2162019-12-2117:34:0057,503,7352019-12-2117:33:007nQ-17-71原始表.png物化視圖I23umall_count123c&untfl)toDateTimetdividefstatisticjimej1000)1；33g2019-12-2117:37:001,10572019-12-2117:35:004,3636912冊(cè)2019-12-2117:35:0029766J552収412019-12-2117:34:005750訓(xùn)827.4982019-12-2117:33:007024784?g物化視圖.png2019-12-2117:32:00阿60449J552019-12-2117:31:00Jin.riro-ic-irun1nw1T.in.rn查看最新的數(shù)據(jù)，