append_vtr: Append rows to an existing .vtr file

In vectra: Columnar Query Engine for Larger-than-RAM Data

Append rows to an existing .vtr file

Description

Appends one or more new row groups to the end of an existing .vtr file without touching or recompressing existing row groups. The schema of x must exactly match the schema of the target file (same column names and types, in the same order).

Usage

append_vtr(x, path, ...)

Arguments

x	A vectra_node (lazy query) or a data.frame.
path	File path of an existing .vtr file to append to.
...	Additional arguments passed to methods.

Details

The operation is not fully atomic: if the process is interrupted after new row groups are written but before the header is patched, the file will be in a corrupted state. Use write_vtr() for safety-critical write-once workloads.

Value

Invisible NULL.

Examples

f <- tempfile(fileext = ".vtr")
write_vtr(mtcars[1:10, ], f)
append_vtr(mtcars[11:20, ], f)
result <- tbl(f) |> collect()
stopifnot(nrow(result) == 20L)
unlink(f)

vectra documentation built on May 8, 2026, 9:06 a.m.