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# slice, head and tail aren't available
Code
lf %>% slice()
Condition
Error in `slice()`:
! `slice()` is not supported on database backends.
---
Code
lf %>% slice_head()
Condition
Error in `slice_head()`:
! `slice_head()` is not supported on database backends.
i Please use `slice_min()` instead.
---
Code
lf %>% slice_tail()
Condition
Error in `slice_tail()`:
! `slice_tail()` is not supported on database backends.
i Please use `slice_max()` instead.
# slice_min handles arguments
Code
db %>% slice_min()
Condition
Error in `slice_min()`:
! `order_by` is absent but must be supplied.
---
Code
db %>% slice_min(id, prop = 0.5, with_ties = FALSE)
Condition
Error in `slice_by()`:
! Can only use `prop` when `with_ties = TRUE`
---
Code
db %>% slice_min(id, n = 1, na_rm = FALSE)
Condition
Error in `slice_min()`:
! `na_rm = FALSE` isn't supported on database backends.
i It must be TRUE instead.
# slice_max orders in opposite order
Code
db %>% slice_max()
Condition
Error in `slice_max()`:
! `order_by` is absent but must be supplied.
---
Code
db %>% slice_max(id, n = 1, na_rm = FALSE)
Condition
Error in `slice_max()`:
! `na_rm = FALSE` isn't supported on database backends.
i It must be TRUE instead.
# slice_* can use data masking pronouns
Code
lf %>% slice_max(x)
Output
<SQL>
SELECT `x`, `id`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `x` DESC) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
Code
lf %>% slice_max(.data$x)
Output
<SQL>
SELECT `x`, `id`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `x` DESC) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
Code
lf %>% slice_max(.data$x * .env$x)
Output
<SQL>
SELECT `x`, `id`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `x` * -1 DESC) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
# slice_sample errors when expected
Code
db %>% slice_sample(replace = TRUE)
Condition
Error in `slice_sample()`:
! Sampling with replacement is not supported on database backends
---
Code
db %>% slice_sample(weight_by = x)
Condition
Error in `slice_sample()`:
! Weighted resampling is not supported on database backends
---
Code
db %>% slice_sample(prop = 0.5)
Condition
Error in `slice_sample()`:
! Sampling by `prop` is not supported on database backends
# check_slice_size checks for common issues
Code
lf %>% slice_sample(n = 1, prop = 1)
Condition
Error in `slice_sample()`:
! Must supply exactly one of `n` and `prop` arguments.
---
Code
lf %>% slice_sample(n = "a")
Condition
Error in `slice_sample()`:
! `n` must be a single number.
---
Code
lf %>% slice_sample(prop = "a")
Condition
Error in `slice_sample()`:
! `prop` must be a single number
---
Code
lf %>% slice_sample(n = -1)
Condition
Error in `slice_sample()`:
! `n` must be a non-missing positive number.
---
Code
lf %>% slice_sample(prop = -1)
Condition
Error in `slice_sample()`:
! `prop` must be a non-missing positive number.
# slice_helper `by` errors use correct error context and correct `by_arg`
Code
slice_min(gdf, order_by = x, by = x)
Condition
Error in `slice_min()`:
! Can't supply `by` when `data` is a grouped data frame.
Code
slice_max(gdf, order_by = x, by = x)
Condition
Error in `slice_max()`:
! Can't supply `by` when `data` is a grouped data frame.
Code
slice_sample(gdf, n = 1, by = x)
Condition
Error in `slice_sample()`:
! Can't supply `by` when `data` is a grouped data frame.
# slice_min/max can order by multiple columns
Code
lf %>% slice_min(tibble(x))
Output
<SQL>
SELECT `x`, `y`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `x`) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
Code
lf %>% slice_min(tibble::tibble(x, y))
Output
<SQL>
SELECT `x`, `y`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `x`, `y`) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
Code
lf %>% slice_min(data.frame(y, x))
Output
<SQL>
SELECT `x`, `y`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `y`, `x`) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
---
Code
lf %>% slice_max(tibble(x))
Output
<SQL>
SELECT `x`, `y`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `x` DESC) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
Code
lf %>% slice_max(tibble::tibble(x, y))
Output
<SQL>
SELECT `x`, `y`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `x` DESC, `y` DESC) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
Code
lf %>% slice_max(data.frame(y, x))
Output
<SQL>
SELECT `x`, `y`
FROM (
SELECT `df`.*, RANK() OVER (ORDER BY `y` DESC, `x` DESC) AS `col01`
FROM `df`
) AS `q01`
WHERE (`col01` <= 1)
# slice_min/max informs if order_by uses c()
Can't use `c()` in `slice_min()`
i Did you mean to use `tibble(x, y)` instead?
|
