Trait IsolationLevel 

pub trait IsolationLevel:
    Sealed
    + Copy
    + Default
    + Send
    + Sync
    + 'static {
    const NAME: &'static str;
    const REFRESH_SNAPSHOT_PER_STATEMENT: bool;
    const FIRST_COMMITTER_WINS: bool;
    const VALIDATES_READS: bool;
}

A transaction isolation level.

Sealed: implementing a new level requires engine support, so this trait is not extensible from outside the crate.

Required Associated Constants

const NAME: &'static str

Human-readable name, used in traces and error messages.

const REFRESH_SNAPSHOT_PER_STATEMENT: bool

Whether a fresh snapshot is taken before each statement rather than once at begin.

const FIRST_COMMITTER_WINS: bool

Whether the engine must check for write-write conflicts against versions committed after this transaction’s snapshot. False only for ReadCommitted, which re-reads the latest version before writing.

const VALIDATES_READS: bool

Whether reads are recorded and re-checked at commit. True only for Serializable.

A const so the engine’s read path can branch on it and have the branch compiled away — the weaker levels emit no read-recording code, register no SIREAD locks, and allocate nothing.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl IsolationLevel for ReadCommitted

const NAME: &'static str = "ReadCommitted"

const REFRESH_SNAPSHOT_PER_STATEMENT: bool = true

const FIRST_COMMITTER_WINS: bool = false

const VALIDATES_READS: bool = false

impl IsolationLevel for RepeatableRead

const NAME: &'static str = "RepeatableRead"

const REFRESH_SNAPSHOT_PER_STATEMENT: bool = false

const FIRST_COMMITTER_WINS: bool = true

const VALIDATES_READS: bool = false

impl IsolationLevel for Serializable

const NAME: &'static str = "Serializable"

const REFRESH_SNAPSHOT_PER_STATEMENT: bool = false

const FIRST_COMMITTER_WINS: bool = true

const VALIDATES_READS: bool = true

impl IsolationLevel for Snapshot

const NAME: &'static str = "Snapshot"

const REFRESH_SNAPSHOT_PER_STATEMENT: bool = false

const FIRST_COMMITTER_WINS: bool = true

const VALIDATES_READS: bool = false