Enum PlanCacheMode 

pub enum PlanCacheMode {
    Disabled,
    ReadThrough,
    ReadOnly,
    WriteOnly,
    Refresh,
}

Controls whether a plan evaluation reads from and/or writes to the plan cache.

Variants

Disabled

Bypasses the cache entirely: no reads and no writes.

ReadThrough

Reads cached responses and writes fresh ones back (the default).

ReadOnly

Reads cached responses but never writes new entries.

WriteOnly

Writes fresh responses but never serves cached ones.

Refresh

Ignores existing entries on read yet writes the recomputed response.

Implementations

impl PlanCacheMode

pub fn from_expr(expr: &Expr) -> Result<Self>

Parses a cache mode from a symbol, string, or plan/atom expression.

pub fn from_name(name: &str) -> Result<Self>

Parses a cache mode from its textual name (e.g. "read-through").

pub fn reads(self) -> bool

Returns true when the mode serves cached responses.

pub fn writes(self) -> bool

Returns true when the mode stores recomputed responses.

Trait Implementations

impl Clone for PlanCacheMode

fn clone(&self) -> PlanCacheMode

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for PlanCacheMode

impl Debug for PlanCacheMode

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

Formats the value using the given formatter.

impl Default for PlanCacheMode

fn default() -> PlanCacheMode

Returns the “default value” for a type.

impl Eq for PlanCacheMode

impl PartialEq for PlanCacheMode

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for PlanCacheMode