collapse.tbl_sql function

Compute results of a query

Compute results of a query

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.

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

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()
  • Maintainer: Hadley Wickham
  • License: MIT + file LICENSE
  • Last published: 2024-03-19