Initial commit

relational-data.Rmd

@@ -235,7 +235,7 @@ Graphically, that looks like:
 knitr::include_graphics("diagrams/join-outer.png")
 ```
 
-The most commonly used join is the left join: you use this whenever you lookup additional data out of another table, because it preserves the original observations even when there isn't a match. The left join should be your default join: use it unless you have a strong reason to prefer one of the others.
+The most commonly used join is the left join: you use this whenever you look up additional data out of another table, because it preserves the original observations even when there isn't a match. The left join should be your default join: use it unless you have a strong reason to prefer one of the others.
 
 Another way to depict the different types of joins is with a Venn diagram:
 
@@ -383,7 +383,7 @@ dplyr                        | SQL
 
 Note that "INNER" and "OUTER" are optional, and often omitted.
 
-Joining different variables between the tables, e.g. `inner_join(x, y, by = c("a" = "b"))` uses a slightly different syntax in SQL: `SELECT * FROM x INNER JOIN y ON x.a = y.b`. As this syntax suggests SQL supports a wide range of join types than dplyr because you can connect the tables using constraints other than equality (sometimes called non-equijoins).
+Joining different variables between the tables, e.g. `inner_join(x, y, by = c("a" = "b"))` uses a slightly different syntax in SQL: `SELECT * FROM x INNER JOIN y ON x.a = y.b`. As this syntax suggests SQL supports a wider  range of join types than dplyr because you can connect the tables using constraints other than equality (sometimes called non-equijoins).
 
 ## Filtering joins {#filtering-joins}