Struct ReadOptions 

#[non_exhaustive]
pub struct ReadOptions {
    pub verify_checksums: bool,
    pub fill_cache: bool,
    pub lower_bound: Option<Vec<u8>>,
    pub upper_bound: Option<Vec<u8>>,
}

How one read or iterator behaves.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

verify_checksums: bool

Verify the checksum of every block read from a table (default true).

Turning it off trades corruption detection for a little CPU; a corrupt block then decodes to an error or to wrong data instead of a crate::ErrorCategory::Corruption error.

fill_cache: bool

Keep the blocks this read loads in the block cache (default true).

A one-off scan sets it to false so it does not evict the working set.

lower_bound: Option<Vec<u8>>

The least key an iterator shows (inclusive); None for no bound. Ignored by point reads and scans, which take their range as arguments.

upper_bound: Option<Vec<u8>>

The key an iterator stops before (exclusive); None for no bound. Ignored by point reads and scans.

Implementations

impl ReadOptions

pub fn with_prefix(self, prefix: &[u8]) -> Self

Bounds an iterator to the keys that start with prefix.

use tessarikv::ReadOptions;

let options = ReadOptions::default().with_prefix(b"user/");
assert_eq!(options.lower_bound.as_deref(), Some(&b"user/"[..]));
assert_eq!(options.upper_bound.as_deref(), Some(&b"user0"[..]));

Trait Implementations

impl Clone for ReadOptions

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 ReadOptions

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

Formats the value using the given formatter.

impl Default for ReadOptions

fn default() -> Self

Returns the “default value” for a type.

impl Eq for ReadOptions

impl PartialEq for ReadOptions

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ReadOptions