sqliteHttpConfig: Configure experimental HTTP VFS behavior (optional)

In RSQLite: SQLite Interface for R

Configure experimental HTTP VFS behavior (optional)

Description

lifecycle::badge("experimental")

Set conservative, process-wide options for the experimental HTTP/HTTPS VFS. These values are read on first open of a remote database in the current process.

Usage

sqliteHttpConfig(
  cache_size_mb = NULL,
  prefetch_pages = NULL,
  fallback_full_download = NULL
)

Arguments

cache_size_mb	Integer megabytes for in-memory page cache. NULL leaves unchanged.
prefetch_pages	Integer pages to prefetch ahead. NULL leaves unchanged.
fallback_full_download	Logical; if TRUE, allow full-download fallback when Range is not available. NULL leaves unchanged.

Details

Options are stored in environment variables so they also affect C-level code:

• RSQLITE_HTTP_CACHE_MB: In-memory page cache size in megabytes (default 4).

• RSQLITE_HTTP_PREFETCH_PAGES: Prefetch this many pages ahead (default 0).

• RSQLITE_HTTP_FALLBACK_FULLDL: If TRUE (default), fall back to full download when the server does not support HTTP Range; if FALSE, open will fail.

Value

A named list of previous values (in R types).

Examples

old <- sqliteHttpConfig(cache_size_mb = 8, prefetch_pages = 1, fallback_full_download = TRUE)
on.exit(do.call(sqliteHttpConfig, old), add = TRUE)
# ... connect with sqliteRemote() ...

RSQLite documentation built on July 1, 2026, 1:06 a.m.