Subset rows using column values

This is a method for the dplyr filter() generic. It generates the WHERE clause of the SQL query.

Usage

# S3 method for tbl_lazy
filter(.data, ..., .by = NULL, .preserve = FALSE)

Arguments

.data

A lazy data frame backed by a database query.

...

<data-masking> Variables, or functions of variables. Use desc() to sort a variable in descending order.

.by

<tidy-select> Optionally, a selection of columns to group by for just this operation, functioning as an alternative to group_by(). For details and examples, see ?dplyr_by.

.preserve

Not supported by this method.

Value

Another tbl_lazy. Use show_query() to see the generated query, and use collect() to execute the query and return data to R.

Examples

library(dplyr, warn.conflicts = FALSE)

db <- memdb_frame(x = c(2, NA, 5, NA, 10), y = 1:5)
db %>% filter(x < 5) %>% show_query()
#> <SQL>
#> SELECT `dbplyr_s9uvuVs7Tn`.*
#> FROM `dbplyr_s9uvuVs7Tn`
#> WHERE (`x` < 5.0)
db %>% filter(is.na(x)) %>% show_query()
#> <SQL>
#> SELECT `dbplyr_s9uvuVs7Tn`.*
#> FROM `dbplyr_s9uvuVs7Tn`
#> WHERE ((`x` IS NULL))