Normalize

This commit is contained in:
Hadley Wickham 2023-03-08 17:28:52 -06:00
parent d42b59e4a8
commit 4a3b6d0640
1 changed files with 2 additions and 3 deletions

View File

@ -412,7 +412,8 @@ flights2 |>
## How do joins work?
Now that you've used joins a few times it's time to learn more about how they work, focusing on how each row in `x` matches rows in `y`.
We'll begin by introducing a visual representation of joins, using the simple tibbles defined below and shown in @fig-join-setup. In these examples we'll use a single key called `key` and a single value column (`val_x` and `val_y`), but the ideas all generalize to multiple keys and multiple values.
We'll begin by introducing a visual representation of joins, using the simple tibbles defined below and shown in @fig-join-setup.
In these examples we'll use a single key called `key` and a single value column (`val_x` and `val_y`), but the ideas all generalize to multiple keys and multiple values.
```{r}
x <- tribble(
@ -626,8 +627,6 @@ df1 |>
If you are doing this deliberately, you can set `relationship = "many-to-many"`, as the warning suggests.
### Filtering joins {#sec-non-equi-joins}
The number of matches also determines the behavior of the filtering joins.