inner_join | R Documentation |
The mutating joins add columns from 'y' to 'x', matching rows based on the keys:
* 'inner_join()': includes all rows in 'x' and 'y'. * 'left_join()': includes all rows in 'x'. * 'right_join()': includes all rows in 'y'. * 'full_join()': includes all rows in 'x' or 'y'.
Filtering joins filter rows from 'x' based on the presence or absence of matches in 'y':
* 'semi_join()' return all rows from 'x' with a match in 'y'. * 'anti_join()' return all rows from 'x' without a match in 'y'.
inner_join(x, y, by = NULL, on = NULL) left_join(x, y, by = NULL, on = NULL) right_join(x, y, by = NULL, on = NULL) full_join(x, y, by = NULL, on = NULL) anti_join(x, y, by = NULL, on = NULL) semi_join(x, y, by = NULL, on = NULL)
x |
A data.table |
y |
A data.table |
by |
(Optional) A character vector of variables to join by. If 'NULL', the default, '*_join()' will perform a natural join, using all variables in common across 'x' and 'y'. A message lists the variables so that you can check they're correct; suppress the message by supplying 'by' explicitly. To join by different variables on 'x' and 'y', use a named vector. For example, 'by = c("a" = "b")' will match 'x$a' to 'y$b'. To join by multiple variables, use a vector with length > 1. For example, 'by = c("a", "b")' will match 'x$a' to 'y$a' and 'x$b' to 'y$b'. Use a named vector to match different variables in 'x' and 'y'. For example, 'by = c("a" = "b", "c" = "d")' will match 'x$a' to 'y$b' and 'x$c' to 'y$d'. |
on |
(Optional)
Indicate which columns in x should be joined with which columns in y.
Examples included:
1. |
A data.table
workers = fread(" name company Nick Acme John Ajax Daniela Ajax ") positions = fread(" name position John designer Daniela engineer Cathie manager ") workers %>% inner_join(positions) workers %>% left_join(positions) workers %>% right_join(positions) workers %>% full_join(positions) # filtering joins workers %>% anti_join(positions) workers %>% semi_join(positions) # To suppress the message, supply 'by' argument workers %>% left_join(positions, by = "name") # Use a named 'by' if the join variables have different names positions2 = setNames(positions, c("worker", "position")) # rename first column in 'positions' workers %>% inner_join(positions2, by = c("name" = "worker")) # the syntax of 'on' could be a bit different workers %>% inner_join(positions2,on = "name==worker")
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.