non-equi-join

问题 I have a dataframe df.sample like this id <- c("A","A","A","A","A","A","A","A","A","A","A") date <- c("2018-11-12","2018-11-12","2018-11-12","2018-11-12","2018-11-12", "2018-11-12","2018-11-12","2018-11-14","2018-11-14","2018-11-14", "2018-11-12") hour <- c(8,8,9,9,13,13,16,6,7,19,7) min <- c(47,59,6,18,22,36,12,32,12,21,47) value <- c(70,70,86,86,86,74,81,77,79,83,91) df.sample <- data.frame(id,date,hour,min,value,stringsAsFactors = F) df.sample$date <- as.Date(df.sample$date,format="%Y-%m-

问题 I have a dataframe df.sample like this id <- c("A","A","A","A","A","A","A","A","A","A","A") date <- c("2018-11-12","2018-11-12","2018-11-12","2018-11-12","2018-11-12", "2018-11-12","2018-11-12","2018-11-14","2018-11-14","2018-11-14", "2018-11-12") hour <- c(8,8,9,9,13,13,16,6,7,19,7) min <- c(47,59,6,18,22,36,12,32,12,21,47) value <- c(70,70,86,86,86,74,81,77,79,83,91) df.sample <- data.frame(id,date,hour,min,value,stringsAsFactors = F) df.sample$date <- as.Date(df.sample$date,format="%Y-%m-

问题 I have a dataframe df.sample like this id <- c("A","A","A","A","A","A","A","A","A","A","A") date <- c("2018-11-12","2018-11-12","2018-11-12","2018-11-12","2018-11-12", "2018-11-12","2018-11-12","2018-11-14","2018-11-14","2018-11-14", "2018-11-12") hour <- c(8,8,9,9,13,13,16,6,7,19,7) min <- c(47,59,6,18,22,36,12,32,12,21,47) value <- c(70,70,86,86,86,74,81,77,79,83,91) df.sample <- data.frame(id,date,hour,min,value,stringsAsFactors = F) df.sample$date <- as.Date(df.sample$date,format="%Y-%m-

问题 I have a dataframe df.sample like this id <- c("A","A","A","A","A","A","A","A","A","A","A") date <- c("2018-11-12","2018-11-12","2018-11-12","2018-11-12","2018-11-12", "2018-11-12","2018-11-12","2018-11-14","2018-11-14","2018-11-14", "2018-11-12") hour <- c(8,8,9,9,13,13,16,6,7,19,7) min <- c(47,59,6,18,22,36,12,32,12,21,47) value <- c(70,70,86,86,86,74,81,77,79,83,91) df.sample <- data.frame(id,date,hour,min,value,stringsAsFactors = F) df.sample$date <- as.Date(df.sample$date,format="%Y-%m-

问题 I found that the Hive does not support non-equi join.Is it just because it is difficult to convert non-equi join to Map reduce? 回答1: Yes, the problem is in current map-reduce implementation. How common equi-join is implemented in MapReduce? Input records are being copied in chunks to the mappers, mappers produce output as key-value pairs, which are collected and distributed between reducers using some function in such way that each reducer will process the whole key, in other words, mapper

问题 I found that the Hive does not support non-equi join.Is it just because it is difficult to convert non-equi join to Map reduce? 回答1: Yes, the problem is in current map-reduce implementation. How common equi-join is implemented in MapReduce? Input records are being copied in chunks to the mappers, mappers produce output as key-value pairs, which are collected and distributed between reducers using some function in such way that each reducer will process the whole key, in other words, mapper

问题 df1 = data.frame(id=1,start=as.Date("2012-07-05"),end=as.Date("2012-07-15")) df2 = data.frame(id=rep(1,1371),date = as.Date(as.Date("2012-05-06"):as.Date("2016-02-05"))) output = dplyr::inner_join(x=df1,y=df2,by="id") %>% filter(date>=start & date<= end) I have two dataframes which have each one about one millions rows and I want to join them by id and then filter so that for each row, value of column date is comprised between value of startdate and enddate. An dplyr::inner_join is not

问题 Suppose I have two dataframes. The first one includes "Date" at which a "Name" issues a "Rec" for an "ID" and the "Stop.Date" at which "Rec" becomes invalid. df (only a part) structure(list(Date = structure(c(13236, 13363, 14074, 13199, 14554), class = "Date"), ID = c("AU0000XINAA9", "AU0000XINAA9", "AU0000XINAC5", "AU0000XINAI2", "AU0000XINAJ0"), Name = c("N+1 BREWIN", "N+1 BREWIN", "ARBUTHNOT SECURITIES LTD.", "INVESTEC BANK (UK) PLC", "AWRAQ INVESTMENTS"), Rec = c(1, 2, 2, 2, 1), Stop.Date

问题 could you please help me out with this: I have a dataframe ( df1 ) that has index of all articles published in the website's CMS. There's a column for current URL and a column of original URLs in case they were changed after publication (column name Origin ): URL Origin ArticleID Author Category Cost https://example.com/article1 https://example.com/article 001 AuthorName Politics 120 USD https://example.com/article2 https://example.com/article2 002 AuthorName Finance 68 USD Next I have an

问题 I am trying to join data.table x to z using a non-equi join. Table x contains two columns X1 and X2 that are used as the range to use for joining with column Z1 in z. The current code successfully does the non-equi join however certain columns are removed or renamed. I would like to return the 'ideal' data.table supplied, instead of the one I currently have which I would have to rename columns or join data further to get the 'ideal' data supplied. > library(data.table) > > x <- data.table(Id