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dbplyr (version 2.4.0)

collapse.tbl_sql: Compute results of a query

Description

These are methods for the dplyr generics collapse(), compute(), and collect(). collapse() creates a subquery, compute() stores the results in a remote table, and collect() executes the query and downloads the data into R.

Usage

# S3 method for tbl_sql
collapse(x, ...)

# S3 method for tbl_sql compute( x, name = NULL, temporary = TRUE, unique_indexes = list(), indexes = list(), analyze = TRUE, ..., cte = FALSE )

# S3 method for tbl_sql collect(x, ..., n = Inf, warn_incomplete = TRUE, cte = FALSE)

Arguments

x

A lazy data frame backed by a database query.

...

other parameters passed to methods.

name

Table name in remote database.

temporary

Should the table be temporary (TRUE, the default) or persistent (FALSE`)?

unique_indexes

a list of character vectors. Each element of the list will create a new unique index over the specified column(s). Duplicate rows will result in failure.

indexes

a list of character vectors. Each element of the list will create a new index.

analyze

if TRUE (the default), will automatically ANALYZE the new table so that the query optimiser has useful information.

cte

[Experimental] Use common table expressions in the generated SQL?

n

Number of rows to fetch. Defaults to Inf, meaning all rows.

warn_incomplete

Warn if n is less than the number of result rows?

Examples

Run this code
library(dplyr, warn.conflicts = FALSE)

db <- memdb_frame(a = c(3, 4, 1, 2), b = c(5, 1, 2, NA))
db %>% filter(a <= 2) %>% collect()

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