Inspect Parquet row groups — row_groups • qio

Inspect Parquet row groups

Usage

row_groups(x, ...)

# S3 method for class 'qio_parquet_file'
row_groups(x, ...)

Arguments

x: A qio_parquet_file object.
...: Reserved for future use.

Value

A data frame with one row per row group and the columns:

row_group: 1-based row-group ID, which is what row_groups = selects on in collect(), read_parquet(), and walk_batches().
rows: Rows in the group.
compressed_bytes, uncompressed_bytes: Total size of the group's column chunks on disk and after decompression.

Counts and sizes are doubles rather than integers, because a row group can exceed .Machine$integer.max.

See also

column_chunks() for the same sizes per column, and column_statistics() for what the writer claims about each chunk.

Examples

path <- tempfile(fileext = ".parquet")
write_parquet(mtcars, path)
pf <- open_parquet(path)
row_groups(pf)
#>   row_group rows compressed_bytes uncompressed_bytes
#> 1         1   32             1805               1805
close_parquet(pf)