Struct Cost 

pub struct Cost {
    pub source: Option<String>,
    pub uncompressed: Option<u64>,
    pub codec: Option<String>,
    pub row_groups: Option<usize>,
    pub partitions: Option<Partitions>,
    pub tables: Option<usize>,
    pub opens_one: bool,
    pub ipc_stream: bool,
}

What pressing Enter on a dataset will cost (200 MB of zstd Parquet is gigabytes in memory, and NFS is not tmpfs), all from what datui already reads: the mount table and the footer.

Fields

source: Option<String>

Filesystem or URL scheme: nfs4, ext4, tmpfs, fuse.sshfs, s3.

uncompressed: Option<u64>

Bytes once decompressed, as against on disk.

codec: Option<String>

Compression codec, as the file itself names it.

row_groups: Option<usize>

Row groups: one huge group cannot be read in parallel or skipped; thousands of tiny ones cost overhead.

partitions: Option<Partitions>

Partition layout, for a hive dataset.

tables: Option<usize>

Tables of its own, for a file of tables: one opens, several are listed.

opens_one: bool

Whether a file of several tables opens one (a workbook’s first sheet): Enter opens it and → lists them.

ipc_stream: bool

An Arrow IPC stream (converted before scanning) rather than an IPC file (scanned in place), from its first bytes.

Trait Implementations

impl Clone for Cost

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Cost

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Cost

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Cost

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for Cost

impl PartialEq for Cost

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for Cost

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Cost