Struct MigrationMeta 

pub struct MigrationMeta {
    pub version: i64,
    pub name: &'static str,
    pub idempotent: bool,
    pub reversible: bool,
    pub data_loss_risk: DataLossRisk,
}

Per-migration metadata record.

Fields

version: i64

Target schema version this migration produces (i.e. the CURRENT_SCHEMA_VERSION value reached AFTER it runs).

name: &'static str

Short human-readable name. Convention: SCREAMING_SNAKE summarising the schema delta (e.g. ADD_TIER, FEDERATION_NONCES).

idempotent: bool

true when re-running the migration against an already- at-target DB is a no-op (uses CREATE ... IF NOT EXISTS, ALTER TABLE ... ADD COLUMN IF NOT EXISTS shapes, or per-row UPDATE WHERE-clauses that match nothing on a second pass).

reversible: bool

true when the migration can be reverted purely by lowering the schema_version row (no data was destroyed, no table was dropped, no UPDATE clobbered a column the prior schema needed).

data_loss_risk: DataLossRisk

Data-loss class on revert. See DataLossRisk.

Trait Implementations

impl Clone for MigrationMeta

fn clone(&self) -> MigrationMeta

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for MigrationMeta

impl Debug for MigrationMeta

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

Formats the value using the given formatter.