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Hadley Wickham
2023-03-08 17:28:52 -06:00
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joins.qmd
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@@ -412,7 +412,8 @@ flights2 |>
## How do joins work? ## 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`. 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} ```{r}
x <- tribble( x <- tribble(
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If you are doing this deliberately, you can set `relationship = "many-to-many"`, as the warning suggests. If you are doing this deliberately, you can set `relationship = "many-to-many"`, as the warning suggests.
### Filtering joins {#sec-non-equi-joins} ### Filtering joins {#sec-non-equi-joins}
The number of matches also determines the behavior of the filtering joins. The number of matches also determines the behavior of the filtering joins.